Pro Series 5 Degree One Piece, No Clamps, Hardware"This one piece mount was specifically designed for the ROK motor. Its rigid structure helps keep vibration at a minimum and the additional option of a copper spacer plate will also help decrease vibration from the motor. The machined fins underneath the mount help dissipate the heat coming off of the motor." Pro Series Mount is specific to 30x90 and 30x92 chassis Standard clamps and Euro clamps are compatible Copper spacer plate to help minimize