CA1384 - windscreen demister

Period remanufactured windscreen demist, which fixes to the inside of the glass with two suction pads, and the electrical element heats the air to rise against the glass. 6 volt draws 4 amps consumption, 12 volt draws 2 amps consumption, 280mm long x 33mm tall, black body. integral on/off switch. (length of cable supplied, requires electrical supply). please specify whether 12volt or 6volt required