The Gardner Bender Circuit Alert Non-Contact Detector Tester detects AC voltage from 50 to 600 volts with flashing and beeping alerts. Its fully insulated tip prevents accidental contact with live wires, enhancing safety. The device includes a self-test to ensure proper function and battery health. Compact and CAT III rated, it fits easily in a shirt pocket and operates on a single AAA battery, making it a reliable tool for quick voltage checks before electrical work.