General Tools VR40 Non-Contact Voltage Detector with Adjustable Sensitivity and 4:1 Infrared Thermometer IRT thermometer features a wide temperature measurement range allowing the industrial tool to be used in many different applications Non-contact voltage detector (NCV) circuit makes a beeping sound and flashes LED when activated The electrical circuit tool is safe for CAT III 600V use; pocket thermometer and NCV detector are the perfect pocket tool Use the electrical tool to checks 110V AC outlets for wiring faults; useful as a DIY home project tool General Tools patent-pending design places the laser thermometer, the NCV sensors and a pocket flashlight on the same end Class II laser product, &lt;1mW power output