To suit .12 to .18 Engines only.Will not be suitable for other engines unless meets below requirementsCrankshaft output thread is 5mm in diameter to accept 5mm thread flywheel axle. Kit includes.2 shoe plastic clutch with spring.2 pin flywheel.Flywheel axle 5mm thread. Clutch Housing 16 Teeth.2 x 10x5x4 Bearings