Old a non-contact induction testing electric pen $ 10.18 AC voltage range AC: 90 - 1000V ~ (red indicator) Working temperature: 0 ~ 40C AC voltage range AC: 24 - 1000V (green indicator) Storage temperature: - 20 ~ 50C Frequency range: 50-60Hz Humidity:80% (non condensing) Alarm mode: sound and light alarm Altitude: < 2000m