
250
500
1000
Distance to Object (mm)
OS543 (10:1)     25        50         100
OS542 (12:1)           21         42          84
Diameter of Spot (mm)
Infrared Thermometers
CAUTION!
 – This product 
is not intended for medical 
use or use on humans
TM
Patented Laser Sighting 
OS540 Series
Starts at
Switch From Circle
Circle or Dot Switchable
To High 
Intensity Dot
$
99
 LCD with Backlight 
 Circle/Dot Laser 
On/Off Switch (OS542)
 Auto Power-Off 
 °C/°F Switchable 
 Field of View;
Model OS542: 12 to 1 
Model OS543: 10 to 1
 Display Hold Function
™
PATENTED
Covered by U.S. and International 
patents and pending applications.
Field of View Diagram
•
OS542, $125.
The OS542 and OS543 are low 
priced infrared, which are ideal for 
education, training and demonstration 
programs. Industrial applications 
include diesel and fleet maintenance, 
electrical, measure ink and dryer 
temperature (screen-printing), 
in-process temperature measurement 
and food safety. Laser sighting helps 
locate target at a distance.
Specifications
Display: 4 digit LCD 
Display 
Field of View:
Target Indicator: Laser dot or circle 
Emissivity:
Power Off: Automatic power 
off after 10 to 15 seconds
Temperature Range:
Accuracy: ±2°C (4°F) or ±2% of rdg 
Resolution:
Repeatability: ±1% of rdg or ±1°C (2°F) 
Storage Conditions:
-10 to 60°C (14 to 140°F), 0 to 75% RH
I
llumination: Backlight by LCD
OS542: 12:1 
OS543: 10:1
OS542: 0.98 (fixed) 
OS543: 0.95 (fixed)
OS542: -20 to 500°C (-4 to 932°F) 
OS543: -30 to 550°C (-22 to 1022°F)
OS542: 0.1°C (0.2°F) 
OS543: 0.5°C (1°F), -9.5 to 199.5ºC/ºF
Operating Ambient:
OS542: 0 to 40°C (32 to 104°F), 
10 to 90% RH 
OS543: 0 to 50°C (32 to 122°F), 
10 to 75% RH
Response Time: 0.5 second 
Battery: 9V alkaline (included) 
Battery Life: Approx 9 hours 
Dimensions:
OS542:
157.5 L x 115 W x 36 mm D 
(6.2 x 4.5 x 1.4") 
OS543: 148 L x 105 W x 42 mm D 
(5.8 x 4.1 x 1.6")
Weight: 180 g (6.3 oz) 
Spectral Response:
6 to 14 micron
OS543, $99.
AVAILABLE FOR FAST DELIVERY!
To Order (Specify Model Number)
Model No. Price Description 
OS542 $125 12:1 infrared thermometer 
OS543 99 10:1 infrared thermometer
Comes complete with 9V battery, carrying pouch, operator’s manual and laser circle 
to dot switchable sighting included (model OS542, OS543 laser dot only).
Ordering Examples: OS542, infrared thermometer, $125. 
OCW-3, OMEGACARE
SM 
extends standard 1-year warranty to a total of 4 years ($31), $125 + 31 = $156.
J-34
J
 

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