Microprocessor controlled current loading capability - a TRUE test of powers and grounds. All the advantages of an incandescent Test Light. Pistol grip handle allows access to difficult areas. Dual Audible Tone and bicolor LED - indicate power, ground or open circuits. Super Bright LED Headlamp - great for working under dash, under hood or behind door panels. Durable - Lifetime warranty A quick check tool that speeds automotive circuit testing on 6, 12, 24 and 42 volt systems. It can be used on late model vehicle systems including Hybrids without fear of damaging computer circuits or deploying air bags. 42 Volt range allows for the testing of Hybrid accessory circuits such as: A/C, power steering, starting/charging and others.