The Fluke 1AC-II VoltAlert™ is a pocket-sized portable AC voltage detector adopting electrostatic field sensing technology. It identifies energized circuits quickly by approaching wires, outlets and terminals without direct physical contact with live conductors. Equipped with patented Voltbeat™ continuous self-test function, the unit automatically verifies its working status after power-on. When AC voltage ranging from 90 V to 1000 V is detected, the tip glows bright red and emits an audible beep; silent mode is available for quiet maintenance environments. Rated CAT IV 1000 V for superior safety protection, it is widely applied to factory electrical maintenance, building electrical construction and household circuit safety inspection. It enables rapid troubleshooting of leakage current, miswiring and live breaker faults, serving as a fundamental safety measuring tool for electricians and equipment maintenance technicians. Batteries are included as standard, with a 2-year official manufacturer warranty.