Voltcraft ms 400 multi tester cat iii 1000v contact less voltage tester voltcraft ms 400 p this product detects the steady state electrostatic field generated by ac voltage via insulation without requiring contact to the bare conductor a red glow at the tip and an acoustic signal indicates the presence of voltage additionally an led light is integrated to provide light for dark corners p voltcraft ms 400 multi tester cat iii 1000v