Sagab 230Y Non Contact Voltage Indicator.The original & still the best, Volt Stick is the leading instrument for safely checking the presence of AC voltage, in walls, fuses, circuit breakers, junc bxs etc.No current flow is needed for correct operation.The red indicator in the tip will illuminate on detection of AC voltage.Volt stick models are fully approved to IEC61010-1 CAT111 1000v AC & CE.