12-4058 Prime Digital AC Line Voltage Meter & Polarity Tester
- Plugs into a standard three prong 120 VAC outlet
- Shows if your appliance is operating in a safe voltage range of 110 to 130 AC Volts
- Protects sensitive equipment like air conditioners, TV's, computers, and battery chargers
- Built-in polarity check warns against potential electrical shock, and tells you if outlet is wired correctly