This kit is designed for a Honda 400ex all year models . We use cork style friction plates which are proven to be very durable. Smooth steel plates & springs that are 10-15% stiffer than stock. One of the durability keys to our clutch kit is the smooth steel plates. "Dimpled or textured" steel plates WILL NOT handle as much H.P. or last as long as smooth steel plates. "Dimples" are concave in shape which reduces surface material causing less contact area which results in premature clutch slippage.