Gold-plated brass terminal posts, one with a red and one with a black knob on a twin base having one part red and one part black, so that the part on the outside of the chassis can be either red or black. Rated 10A at 250V. Each post has a 4mm top socket and a 2 1mm dia. Hole in post. Knob size 16 x 15mm dia. Fits panels from 1 2mm dia. To 7mm thick. Panel cut-out requires two 12 7mm holes on 18 5mm centres. Bezel size 35mm x 16mm.