Digital MegOhm Meter Insulation Tester VC60B+ DCV ACV resistance Dual Alarm: sound and light. The display returns to zero when a shortcut resistance occurred, to prevent burning underground. The special design of the battery Monte easily. An insulation tester accurate, reliable and easy to use. rge LCD screen, LCD backlight ON / OFF key, easy to read. Strong anti-magnetic and anti functional disturbance. Full function protection, high voltage anti circuit design. High voltage and short alarm input.