The Stanley Intelli Tools FatMax Non-Contact Voltage Detector can be used to detect voltage or non-contact metals up to 20mm. Allows you to check voltage in a circuit without contact. The integrated sensitivity adjustment allows you to narrow down the search area of live voltage. Specification: AC Voltage Range: 20-1000V. Metal Detecting Distance: <20mm. Safety Rating: CAT III 600V & CAT II 1000V.