Allows operators to test for continuity, shorts,ÿgrounds or the presence of voltage quickly,ÿeffectively and economically. Designed to verify electrical connection of less than 0.1 ohms. Quickly tests that connection is secure and high-quality, and not being compromised. Audible signal and LED illumination alerts user immediately with test results. Operates on 2 standard AA alkaline batteries; rechargeable NiCad batteries can also be used. Low battery pulsing audio and visual indication indicating low batteries needing replacement. Rugged extruded aluminum case is durable, providing long life. Can be easily calibrated with the 35106 Calibration Unit. Easy to verify accuracy and perform adjustment. Made in America