Voltage tester kit to verify the presence of AC (alternating current) voltage prior to working on any application. Audible and 360 visual indication. Patented battery self-test feature. Frequency of 50 to 60 hertz, not adjustable. CAT rating III 1000V (volts), IV 600V. Tests standard and GFCI (ground fault circuit interrupter) outlets. Neon lamps indicate 7 common wiring errors. Wiring errors legend is listed on top and bottom of tester. Compact, ergonomic design with over-molded rubber grips and pocket clip. No. STK001: Type: Non-Contact, AC Voltage: 50 to 1000VAC, Powered By: 1 AAA Battery, Lead Length: N/A, UL Listed: Yes, ETL Listed: No, Pkg Qty: 1, Package Type: Clamshell