It can alarm when it sensed voltage. It need not to contact any steel parts of the electric circuit. It can sense voltage across cable wrap.It can sensed voltage with in several centimeters. So It is very safe voltage test pencil.
Non-contact, need not to contact steel parts of electric circuit. So it is very safe.
It can sensor volt and alarm with in 1 to 20 cm decide by voltage. Across the cable wrap.
Very sensitive, It can alarm even close to network cable and USB cable.
Require 2 AAA batteries, Not include
Sound and LED light alert alarm When it sensed voltage.