This is a cable that converts from an AC adapter to alligator clips. Connector: Male/Female - Male/Female Power plug capacity: 3 Amps Maximum voltage: 12 Volts Outer diameter: 5.5mm, Inner diameter: 2.1mm Polarity: Inside → Red cable (+), Outside → Black cable (-) Used to check the operation of a removed car navigation/head unit. There are no operational problems. I hope someone who needs it can use it.