Electric Socket Wall AC Power Outlet Voltage Detector Sensor Tester Pen 90-1000V generation AC non-contact voltage testers are easy to use - just the tip to a terminal strip, outlet, or supply cord. When the tip glows red and the unit beeps, you know there is voltage present. Electricians, maintenance, service, safety personnel, and homeowners can quickly test for energized circuits in the workplace or . A perfect tool kit for home and electric industry uses. perfect design for testing power cables, , wall sockets, junction boxes, fuses, etc Frequency Range: 50 to 500 Hz Test Voltage Range: 90-1000V AC Safety Rating : CAT II 1000v Powered By: 2 x AAA Batteries (Not included) Just the button, white LED light can be always on when there is absence of voltage Net weight: 40g/Pcs Colour:yellow Material:ABS plastic Size:152 x 22 x 17mm Package Contents: 4 * LED Light Voltage Alert Pen(Don't included battery) Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.