One set of 7mm scale BR style speedometer drive cranks in stainless steel, designed for Slaters driving wheels. Both crankpins are retained by an M1.6 flanged screws at the rear. The crank arm pin has a machined hexagonal end over which the crank arm locates with a hexagonal cutout. Locked in place with an M1.6 flanged screw, no soldering is required. Crank arm is 5.8mm long. 14BA Nut Spinner needed for assembly.