USB Charger - Round - Dual Port - 2x 2.1A - With Voltmeter

Description Panel Mount USB Charger with 2x 2.1 Amp USB charging ports and a built in Volt meter Dimensions OD (Size of hole) - 29mm Depth - 35mm NOTE: This socket is not reverse polarity protected. If you connect the wires incorrectly it will go POP. The poles are clearly market at the back with a + and - , make sure you connect it correctly.