Klein + Hummel M 51 D Installation & Operation Manual

058-E0008
Version 04/05

Installation

Operation

Installation

Operation

KLEIN + HUMMEL GmbH

Zeppelinstrasse 12 • 73760 Ostfildern/Germany

Tel.: + 49/(0)711/ 45893 - 0
Fax: + 49/(0)711/ 45893 - 35
eMail: [e-mail]
Internet: www.klein-hummel.com

KLEIN + HUMMEL GmbH

Zeppelinstrasse 12 • 73760 Ostfildern/Germany

Tel.: + 49/(0)711/ 45893 - 0
Fax: + 49/(0)711/ 45893 - 35
eMail: [e-mail]
Internet: www.klein-hummel.com

Active Control Monitor

M 51 D

058-E0008
Version 04/05

Active Control Monitor

M 51 D

1. Safety Instructions

It is absolutely essential that you read these safety
instructions carefully before connecting and using this
K+H product. Your safety depends on it. Furthermore,
failure to follow these instructions voids the warranty. To

ensure safe operation for years to come, keep these
instructions in a safe place for future reference. K+H has
manufactured this product in accordance with IEC 1992 (SEC)
39 standards, then tested and delivered it in safe operating
condition. To maintain it in this condition, you must:

€ observe all safety instructions,
€ use the product only as described herein,
€ have any maintenance, repairs, or modifications performed

only by K+H or other authorized personnel, and

€ ensure that the room in which you use this product is wired

in accordance with the local electrical code.

Warning!

€ When the interior of the cabinet is exposed, touching some

parts can lead to an electric shock.

€ If you need to gain access to the interior electronics of the

unit, always disconnect the unit from any and all power
sources first.

€ Any repairs, maintenance, or other service of the unit when

its interior compartment is exposed may only be performed
safely (in accordance with VBG 4) by authorized technicians
familiar with all the risks involved. Even in an unplugged
state, a fully charged capacitor in the unit can zap the
unsuspecting.

€ Loudspeaker output jacks labeled with the IEC 417/5036

emblem (Fig. A, right) may be carrying dangerously high
voltages. If your unit has this emblem, ensure that any
connections to be made between these jacks and the
speakers themselves are made before powering up the
unit, and are done so only with manufacturer-approved
interconnecting cables.

€ If you need to replace any fuses, ensure that the

replacements are of exactly the same type, value and
voltage as the originals, as spelled out in the technical

specifications at the rear of this manual.
€ Do not use "repaired" fuses.
€ If you do not have any fuses on hand of the specified size,

type, and value, do not hot-wire the contacts in the holder

by short-circuiting them.
€ Certain areas of the cabinet, cover, and rear panel can

achieve extreme temperatures and are therefore marked

with a "HOT" label (Fig. B). Refrain from touching any heat

sink or ventilation grille.
€ High volume levels are known to cause permanent - i.e.

irreversible - hearing damage, especially when listened to

without sufficient breaks. The higher the levels, the more

frequent and extended must be the breaks. Avoid standing

too close to loudspeakers that are being driven at high

levels. If you must be exposed to high sound pressure levels

over an extended period of time, use hearing protection.

Mains Connection:

€ This unit is designed for continuous operation.
€ Ensure that the operating voltage of the unit matches that

of the local mains current (AC line voltage).

1. Safety Instructions

It is absolutely essential that you read these safety
instructions carefully before connecting and using this
K+H product. Your safety depends on it. Furthermore,
failure to follow these instructions voids the warranty. To

ensure safe operation for years to come, keep these
instructions in a safe place for future reference. K+H has
manufactured this product in accordance with IEC 1992 (SEC)
39 standards, then tested and delivered it in safe operating
condition. To maintain it in this condition, you must:

€ observe all safety instructions,
€ use the product only as described herein,
€ have any maintenance, repairs, or modifications performed

only by K+H or other authorized personnel, and

€ ensure that the room in which you use this product is wired

in accordance with the local electrical code.

Warning!

€ When the interior of the cabinet is exposed, touching some

parts can lead to an electric shock.

€ If you need to gain access to the interior electronics of the

unit, always disconnect the unit from any and all power
sources first.

€ Any repairs, maintenance, or other service of the unit when

its interior compartment is exposed may only be performed
safely (in accordance with VBG 4) by authorized technicians
familiar with all the risks involved. Even in an unplugged
state, a fully charged capacitor in the unit can zap the
unsuspecting.

€ Loudspeaker output jacks labeled with the IEC 417/5036

emblem (Fig. A, right) may be carrying dangerously high

voltages. If your unit has this emblem, ensure that any

connections to be made between these jacks and the

speakers themselves are made before powering up the

unit, and are done so only with manufacturer-approved

interconnecting cables.
€ If you need to replace any fuses, ensure that the

replacements are of exactly the same type, value and

voltage as the originals, as spelled out in the technical

specifications at the rear of this manual.
€ Do not use "repaired" fuses.
€ If you do not have any fuses on hand of the specified size,

type, and value, do not hot-wire the contacts in the holder

by short-circuiting them.
€ Certain areas of the cabinet, cover, and rear panel can

achieve extreme temperatures and are therefore marked

with a "HOT" label (Fig. B). Refrain from touching any heat

sink or ventilation grille.
€ High volume levels are known to cause permanent - i.e.

irreversible - hearing damage, especially when listened to

without sufficient breaks. The higher the levels, the more

frequent and extended must be the breaks. Avoid standing

too close to loudspeakers that are being driven at high

levels. If you must be exposed to high sound pressure levels

over an extended period of time, use hearing protection.

Mains Connection:

€ This unit is designed for continuous operation.
€ Ensure that the operating voltage of the unit matches that

of the local mains current (AC line voltage).

€ Always check before connecting the power cable to the

mains socket that the power switch on the unit itself is set
to off ("O").

€ Use the power cable or power supply that came with the

unit to connect to the mains socket (wall outlet).

€ Power supply: a damaged power cable may not be repaired.

Use a new cable.

€ Avoid plugging the mains cable into a power strip that

already has several other power-consuming devices
connected to it.

€ Avoid using extension cables. The unit must be connected

to a mains socket close to it, and that socket should be
freely accessible.

Installation:

€ This product may only be placed on a stable, clean, hori-

zontal surface.
€ Do not expose this product to vibration.
€ Do not operate this product anywhere near water or other

liquids. Do not use it near a sink, swimming pool, bathtub,

or in any damp room or area. Electrical shocks carried

through water can kill. Do not place any beverages

whatsoever on or near this product, as liquids can kill

electronic components.
€ Ensure sufficient ventilation around the product to allow

for adequate heat dissipation, especially near the rear panel

and the sides of the cabinet (minimum of 8 inches from the

nearest wall). The unit may only be installed in a rack if

measures are taken to ensure sufficient ventilation and if

the mounting instructions of the manufacturer are followed.

Do not block or cover any heat sink, fan, or vent.

€ Do not place the product where it will be in the path of

direct sunlight, and keep it a safe distance away from
radiators and other heaters of any kind.

€ If you bring this product from a cold environment into a

warm one (such as from a vehicle into a studio), it is quite
possible that condensation will form inside the cabinet.
Please allow the unit sufficient time for acclimatisation to
room temperature (minimum thirty minutes) before
connecting and powering up.

€ To avoid accidents, do not use any accessory equipment

with this product which is not approved by the manufacturer,
particularly mounting accessories. Do not place this unit
on any unstable platform, cart, stand or table. Should the
unit fall, it can cause bodily injury to persons, or can be
damaged itself.

€ To protect this product from lightning damage during a

thunderstorm or from power surges during an extended
absence, disconnect the power cable from the wall outlet.

Fig. BFig. A

€ Always check before connecting the power cable to the

mains socket that the power switch on the unit itself is set

to off ("O").
€ Use the power cable or power supply that came with the

unit to connect to the mains socket (wall outlet).
€ Power supply: a damaged power cable may not be repaired.

Use a new cable.
€ Avoid plugging the mains cable into a power strip that

already has several other power-consuming devices

connected to it.
€ Avoid using extension cables. The unit must be connected

to a mains socket close to it, and that socket should be

freely accessible.

Installation:

€ This product may only be placed on a stable, clean, hori-

zontal surface.
€ Do not expose this product to vibration.
€ Do not operate this product anywhere near water or other

liquids. Do not use it near a sink, swimming pool, bathtub,

or in any damp room or area. Electrical shocks carried

through water can kill. Do not place any beverages

whatsoever on or near this product, as liquids can kill

electronic components.
€ Ensure sufficient ventilation around the product to allow

for adequate heat dissipation, especially near the rear panel

and the sides of the cabinet (minimum of 8 inches from the

nearest wall). The unit may only be installed in a rack if

measures are taken to ensure sufficient ventilation and if

the mounting instructions of the manufacturer are followed.

Do not block or cover any heat sink, fan, or vent.

€ Do not place the product where it will be in the path of

direct sunlight, and keep it a safe distance away from
radiators and other heaters of any kind.

€ If you bring this product from a cold environment into a

warm one (such as from a vehicle into a studio), it is quite
possible that condensation will form inside the cabinet.
Please allow the unit sufficient time for acclimatisation to
room temperature (minimum thirty minutes) before
connecting and powering up.

€ To avoid accidents, do not use any accessory equipment

with this product which is not approved by the manufacturer,
particularly mounting accessories. Do not place this unit
on any unstable platform, cart, stand or table. Should the
unit fall, it can cause bodily injury to persons, or can be
damaged itself.

€ To protect this product from lightning damage during a

thunderstorm or from power surges during an extended
absence, disconnect the power cable from the wall outlet.

Fig. BFig. A

2. Installation

2.1. Power source

The amplifier electronics of the standard European model
are set up for an AC line voltage of 230 volts, 50 or 60 Hz.
Export versions with other voltages are also available.
Additionally operation from a 12 to 14 V DC source is
provided. The DC connectors (6.35 mm flat plugs) are hidden
under a plastic cover. A non reversable plug case is delivered
with the speaker. Be sure of the correct polarity as shown on
the imprint. A protection diode prevents from damage caused
by wrong polarity.

2.2 Operating conditions

The K+H model M 51 D active control monitor is intended for
use over a range of ambient temperatures from +10° C to
+40° C (+50° F to +104° F). During transport or storage,
temperatures from -25° C to +70° C (-13° F to 158° F) are
permissible.

2.3. Input selector "SELECT"

The input selector determines the kind of input operating mode.
Since one digital input carries both stereo channels, the input
selector switch has four positions: analog mode, digital mode
left channel (DIG. L), digital mode mono summed from both
left and right channels (L+R) and digital mode right channel
(R). Simultaneous operation from one analog and one digital
audio source is not possible. At any given time you may connect
only one type of source to the pair.

2.4 Input analog XLR

The sensitivity of the transformer-balanced floating input is
+6 dBu (1.55 volts rms). The three-pin female XLR jack is wired
in the standard manner (pin 1 = ground, pin 2 = +, pin 3 = -).
If you are connecting unbalanced analog sources, you will
need to solder a bridge between pins 1 and 3:

unbalanced balanced

as seen from the solder terminals of male XLR

Please observe, that the analog input level does not exceed
7 volts rms.
Very important: even during analog operation, the BNC
connection should be terminated with the included
75-Ohms resistor.

2. Installation

2.1. Power source

The amplifier electronics of the standard European model
are set up for an AC line voltage of 230 volts, 50 or 60 Hz.
Export versions with other voltages are also available.
Additionally operation from a 12 to 14 V DC source is
provided. The DC connectors (6.35 mm flat plugs) are hidden
under a plastic cover. A non reversable plug case is delivered
with the speaker. Be sure of the correct polarity as shown on
the imprint. A protection diode prevents from damage caused
by wrong polarity.

2.2 Operating conditions

The K+H model M 51 D active control monitor is intended for
use over a range of ambient temperatures from +10° C to
+40° C (+50° F to +104° F). During transport or storage,
temperatures from -25° C to +70° C (-13° F to 158° F) are
permissible.

2.3. Input selector "SELECT"

The input selector determines the kind of input operating mode.
Since one digital input carries both stereo channels, the input
selector switch has four positions: analog mode, digital mode
left channel (DIG. L), digital mode mono summed from both
left and right channels (L+R) and digital mode right channel
(R). Simultaneous operation from one analog and one digital
audio source is not possible. At any given time you may connect
only one type of source to the pair.

2.4 Input analog XLR

The sensitivity of the transformer-balanced floating input is
+6 dBu (1.55 volts rms). The three-pin female XLR jack is wired
in the standard manner (pin 1 = ground, pin 2 = +, pin 3 = -).
If you are connecting unbalanced analog sources, you will
need to solder a bridge between pins 1 and 3:

unbalanced balanced

as seen from the solder terminals of male XLR

Please observe, that the analog input level does not exceed
7 volts rms.
Very important: even during analog operation, the BNC
connection should be terminated with the included
75-Ohms resistor.

In digital mode, this same XLR input accepts the digital signal
according to the AES/EBU specification (110 Ohm balanced).

2.5 Digital inputs BNC, XLR

The BNC digital input configured as a 75-Ohm connector, is
intended to receive signal sources in S/P-DIF or AES 3id
format. The incoming digital signal line requires one 75-Ohm
terminator at the very end, as the M 51 D has no internal
termination. The XLR input and the BNC input are wired in
parallel across a transformer. The fact that the termination is
wired externally allows you to make connections in a wide
variety of ways:

2.5.1 Source 1x AES/EBU, Monitors connected with
each other via BNC cable

2.5.2 Source 2x AES/EBU

2.5.3 Source 1x S/P-DIF, AES 3id, connection using
two T-connectors

In digital mode, this same XLR input accepts the digital signal
according to the AES/EBU specification (110 Ohm balanced).

2.5 Digital inputs BNC, XLR

The BNC digital input configured as a 75-Ohm connector, is
intended to receive signal sources in S/P-DIF or AES 3id
format. The incoming digital signal line requires one 75-Ohm
terminator at the very end, as the M 51 D has no internal
termination. The XLR input and the BNC input are wired in
parallel across a transformer. The fact that the termination is
wired externally allows you to make connections in a wide
variety of ways:

2.5.1 Source 1x AES/EBU, Monitors connected with
each other via BNC cable

2.5.2 Source 2x AES/EBU

2.5.3 Source 1x S/P-DIF, AES 3id, connection using
two T-connectors

2.5.5 Source 2x S/P-DIF, AES 3id

2.6 Mains and battery fuses

The mains fuse is to be found on the rear panel, close to
mains connector whereas the battery fuse is only accessible
after removing the rear panel. Before changing fuses all po­wer sources have to be disconnected. Only the following
fuses 5x20 mm may be used:

mains 230 V AC 0.2 A slow blow
mains 117 V AC 0.4 A slow blow
mains 100 V AC 0.5 A slow blow
battery 12 - 14 V DC 2.5 A slow blow

2.7 Speaker placement

The loudspeaker chassis used in the M 51 D is magnetically
shielded, so you are free to set the speakers right next to a
video monitor without needing to worry about adversely
affecting the screen. The sophisticated M 51 D design gained
in an unified and neutral sound within the nearfield zone. Best
results are achieved within a hearing distance of 1 to 1.5 m.
Stereo pairs should be turned to the hearing area.
On the bottom there is a 3/8" threaded bushing for mounting
the M 51 D on a standard microphone tripod. The LH 11 table
mount bracket can be fixed to the two M6 threaded holes in
the sides and so allows rotation around horizontal and verti­kal axis.

2.8 Ground lift

Since the input is transformer - balanced and floating, you
should rarely experience any hum. In unusual cases, or if the
source is unbalanced, it may be necessary to lift the connection
between signal ground and chassis ground (connected to
protective earth, PE), in which case you will find a wire bridge
inside the amplifier - see figure beside. On delivery the shown
connection is closed and can be opened if a hum interference
occurs.

Warning!
Never disconnect the protective earth (PE) of the mains
power cable from the chassis ground!

3. Operation

2.5.5 Source 2x S/P-DIF, AES 3id

2.6 Mains and battery fuses

The mains fuse is to be found on the rear panel, close to
mains connector whereas the battery fuse is only accessible
after removing the rear panel. Before changing fuses all po­wer sources have to be disconnected. Only the following
fuses 5x20 mm may be used:

mains 230 V AC 0.2 A slow blow
mains 117 V AC 0.4 A slow blow
mains 100 V AC 0.5 A slow blow
battery 12 - 14 V DC 2.5 A slow blow

2.7 Speaker placement

The loudspeaker chassis used in the M 51 D is magnetically
shielded, so you are free to set the speakers right next to a
video monitor without needing to worry about adversely
affecting the screen. The sophisticated M 51 D design gained
in an unified and neutral sound within the nearfield zone. Best
results are achieved within a hearing distance of 1 to 1.5 m.
Stereo pairs should be turned to the hearing area.
On the bottom there is a 3/8" threaded bushing for mounting
the M 51 D on a standard microphone tripod. The LH 11 table
mount bracket can be fixed to the two M6 threaded holes in
the sides and so allows rotation around horizontal and verti­kal axis.

2.8 Ground lift

Since the input is transformer - balanced and floating, you
should rarely experience any hum. In unusual cases, or if the
source is unbalanced, it may be necessary to lift the
connection between signal ground and chassis ground
(connected to protective earth, PE), in which case you will
find a wire bridge inside the amplifier - see figure beside. On
delivery the shown connection is closed and can be opened
if a hum interference occurs.

Warning!
Never disconnect the protective earth (PE) of the mains
power cable from the chassis ground!

3.1 Power switch

The power switch on the front side
activates the power supply of the
amplifier from both mains and battery
sources. AC and DC - input may be
connected simultaneously. A LED in
the switch indicates, that the control
monitor is ready.

3.3 Volume control

The volume control on the front side
can be set down to minus infinity.

3.2 Monitoring loudness

The M 51 D is designed for nearfield monitoring. For best
performance and reliability it is recommended to avoid
exessive boosting of bass and treble by extern sound contols
due to large monitoring distances or bad positioning.

4. Warranty

All K+H products undergo an extensive round of quality control
testing before ever leaving the factory. Before the semicon­ductors are mounted on the circuit board, they are subjected
to rigorous tests. Every single loudspeaker is guaranteed to
match its technical specifications within strict tolerance
standards for the series.
Store the original carton in a safe, dry place. If you should
ever need warranty service, pack the loudspeaker in its origi­nal packing materials and carton together with a detailed
description of the problem and ship it (freight prepaid) to:

KLEIN + HUMMEL GmbH
Customer service
Zeppelinstrasse 12
73760 Ostfildern / Germany

All component parts of the amplifier with exception of the
semiconductors are covered under this warranty for a period
of twelve months from date of purchase. Parts will be replaced
at no charge if their failure was due to a material defect. Not
covered under this warranty are damages due to improper
handling, installation, operation, spikes or surges in the mains
voltage, and failure to follow the installation and operating
instructions contained in this manual.
In the event warranty service is required, presentation of a
warranty card will not be necessary. Proof of purchase date
can be made by way of appropriate documents (invoice,
packing slip, delivery receipt).

3. Operation

3.1 Power switch

The power switch on the front side
activates the power supply of the
amplifier from both mains and battery
sources. AC and DC - input may be
connected simultaneously. A LED in
the switch indicates, that the control
monitor is ready.

3.3 Volume control

The volume control on the front side
can be set down to minus infinity.

3.2 Monitoring loudness

The M 51 D is designed for nearfield monitoring. For best
performance and reliability it is recommended to avoid exessive
boosting of bass and treble by extern sound contols due to
large monitoring distances or bad positioning.

4. Warranty

All K+H products undergo an extensive round of quality
control testing before ever leaving the factory. Before the
semicon-ductors are mounted on the circuit board, they are
subjected to rigorous tests. Every single loudspeaker is
guaranteed to match its technical specifications within strict
tolerance standards for the series.
Store the original carton in a safe, dry place. If you should
ever need warranty service, pack the loudspeaker in its origi-

nal packing materials and carton together with a detailed
description of the problem and ship it (freight prepaid) to:

KLEIN + HUMMEL GmbH
Customer service
Zeppelinstrasse 12
73760 Ostfildern / Germany

All component parts of the amplifier with exception of the
semiconductors are covered under this warranty for a period
of twelve months from date of purchase. Parts will be replaced
at no charge if their failure was due to a material defect. Not
covered under this warranty are damages due to improper
handling, installation, operation, spikes or surges in the mains
voltage, and failure to follow the installation and operating
instructions contained in this manual.
In the event warranty service is required, presentation of a
warranty card will not be necessary. Proof of purchase date
can be made by way of appropriate documents (invoice,
packing slip, delivery receipt).

Specifications M 51 D

Free-field frequency response 110 Hz - 20 kHz ± 5 dB
Self generated noise @ 10 cm 20 dB (A)
Total harmonic distortion

above 350 Hz < 1 % @ 80 dB / SPL / 1m

Max. sound pressure level

in half-space, 3% THD 100 dB/SPL
averaged between 100 Hz and 6 kHz

Electronics

Amplifier power output
Mains operation 14 W 4 Ohm THD < 0.1 %
Battery operation 12 volts 10 W 4 Ohm THD < 0.1 %
Battery operation 14 volts 14 W 4 Ohm THD < 0.1 %

Equalization optimized for near field

monitoring

Analog Input

Connector XLR 3
Impedance 20 kOhm, transformer-

balanced and floating
Sensivity + 6 dBu (1.55 volts)
Volume control 0...-infinite dB
CMRR > 50 dB @15 kHz

Digital inputs

Connectors, standards XLR: AES / EBU

BNC: S / P - DIF, AES 3id
Impedance XLR-connector 110 Ohm transformer

balanced and floating
Impedance BNC-connector 75 Ohm unbalanced

Input selector switch analog / digital left,

digital left + right, digital right

Analog - digital converter

Resolution, type 24 Bit DA, delta sigma
Sampling rate 32 - 48 kHz,

256x oversampling

Mains, connector 230 volts AC, 50/60 Hz

3 - terminal Euro connector

Battery, connector 12 - 14 volts DC

6.35 x 0.8 mm flat plug x2

Power consumption

Idle mains operation 4 VA
Full power mains operation 30 VA
Full power battery operation 14 v 1.8 A

Fuses

Mains 230 volts AC 0.2 A slow blow
Mains 117 volts AC 0.4 A slow blow
Mains 100 volts AC 0.5 A slow blow
Battery 12 - 14 volts DC 2.5 A slow blow

Dimensions

W x H x D 120 x 173 x 116 mm

Volume 2.4 litres
Weight 2.3 kg
Driver magnetically shielded 75 mm / 3"
Mounting options 3/8" threaded bushing on

bottom, 2x M6 on sides

Mounting adaptors LH 11 table mount bracket
Cabinet

Material aluminium
Finish lacquered charcoal-grey

(RAL 7021), others optional
(add - on price)

Baffle cover fixed metal grille

Specifications M 51 D

Free-field frequency response 110 Hz - 20 kHz ± 5 dB
Self generated noise @ 10 cm 20 dB (A)
Total harmonic distortion

above 350 Hz < 1 % @ 80 dB / SPL / 1m

Max. sound pressure level

in half-space, 3% THD 100 dB/SPL

Electronics

Amplifier power output
Mains operation 14 W 4 Ohm THD < 0.1 %
Battery operation 12 volts 10 W 4 Ohm THD < 0.1 %
Battery operation 14 volts 14 W 4 Ohm THD < 0.1 %

Equalization optimized for near field

monitoring

Analog Input

Connector XLR 3
Impedance 20 kOhm, transformer-

balanced and floating
Sensivity + 6 dBu (1.55 volts)
Volume control 0...-infinite dB
CMRR > 50 dB @15 kHz

Digital inputs

Connectors, standards XLR: AES / EBU

BNC: S / P - DIF, AES 3id
Impedance XLR-connector 110 Ohm transformer

balanced and floating
Impedance BNC-connector 75 Ohm unbalanced

Input selector switch analog / digital left,

digital left + right, digital right

Analog - digital converter

Resolution, type 24 Bit DA, delta sigma
Sampling rate 32 - 48 kHz,

256x oversampling

Mains, connector 230 volts AC, 50/60 Hz

3 - terminal Euro connector

Battery, connector 12 - 14 volts DC

6.35 x 0.8 mm flat plug x2

Power consumption

Idle mains operation 4 VA
Full power mains operation 30 VA
Full power battery operation 14 v 1.8 A

Fuses

Mains 230 volts AC 0.2 A slow blow
Mains 117 volts AC 0.4 A slow blow
Mains 100 volts AC 0.5 A slow blow
Battery 12 - 14 volts DC 2.5 A slow blow

Dimensions

W x H x D 120 x 173 x 116 mm

Volume 2.4 litres
Weight 2.3 kg
Driver magnetically shielded 75 mm / 3"
Mounting options 3/8" threaded bushing on

bottom, 2x M6 on sides

Mounting adaptors LH 11 table mount bracket
Cabinet

Material aluminium
Finish lacquered charcoal-grey

(RAL 7021), others optional
(add - on price)

Baffle cover fixed metal grille