BYKES Super Fast Ultra Compact Pocket Infrared Professional IR Thermometer - 1 Second Response Time - (Upto 428&deg;f) Ultra compact size infrared thermometers with excellent reading stability and accuracy 1 second response time - New Low voltage technology, no need for 9V battery Compact Size, With pocket clip, Place in shirt pocket like a pen. fast and fun to check temperatures of unknown surfaces - Range: From -27 to 428F National Lab Standard Traceable, IR-SoC technology (Infrared System on Chip)