For easiest installation, work with the chair upside down. Carefully remove the bottom cover and unscrew the frame from the seat. Remove the old spacers and mount the new ones on the frame. Place the plate between the frame and the seat and match the holes for the screws, the groove in the plate should be down towards the floor. Then tighten the screws by hand with a wrench. If your chair has no upholstery, use the included 3 cm screw, if the chair has original upholstery, use the included 3.5 cm screw.