Tilt Swivel Rocker Seat Plate Mechanism W Spindle Cartridge Post Shaft Universal. Listing is for a NEW combination 6" x 10" mounting holes seat plate (SP-610) and 9" x 1.1" diameter spindle (CC-9) including bearing and all hardware for complete installation. If you are tired of trying to take these 2 parts apart, then this kit is for you. Just make sure you have the same mounting holes seat plate and that your spindle is 9.2" long plus or minus 0.5". If your spindle is still inside your seat plate, just measure the length of the exposed part and add 1". WARNING: DO NOT ATTEMPT INSTALLATION IF YOUR SPINDLE EXCEEDS 9.2" BY MORE THAN 0.5". This set will replace any and all brands regardless of where you purchased the chair.