HPI shock parts set tree. These are the nylon parts that make up the shocks. Constructed of black nylon. This product includes four spring retainers. Eight spring spacers. Two body posts. Four shock caps. Four shock body bottoms. Four bottom spring retainers. Four shock ball ends. Six nylon rods. Two long rod ball cups. Two braces. These shock parts are for the following vehicles: RS4 Pro 3, Sport 2, Nitro 2, Racer 2, and RTR Nitro.