Hioki leads the industry in non-metallic contact test and measurement technology that promotes safety on the worksite. The Hioki 3481 is a pen-style, non-metallic contact voltage detector with a bright LED light that promotes safety and work efficiency even in dim worksites. When voltage is detected, the LED lights red along with an audio signal. Non-contact detection of AC voltage from 40 V to 600 V with bright LED light. Pen-style, a compact detector with pocket clip. 40 V to 600 V AC (When brought into contact with a 2 mm^2 insulated cable equivalent to 600 V polyvinyl chloride insulated wire), Maximum sensitivity variable range 40 V to 80 V AC (80 V at the time of shipment). The operating frequency is 50 Hz/ 60 Hz. Red LED lights up and the buzzer sounds when the wire is live. White LED is dim or out when the batteries are low. The power will be turned off automatically if the instrument remains idle for 3 minutes after the power is turned on. LR44 button alkaline batteries ×3, Continuous use 5 hr (Power ON standby state).