Fitment: For Mazda Miata MX-5 NA NB NC ND 1990-2021 Type: Door Bushings Material :POM & CNC Machined Bushings Thick: 16 mm Quite possibly the easiest and most effective way to improve your Miata experience! This is a high quality, professionally CNC Machined product, made on an industrial CNC Vertical Milling Machine. Guaranteed tolerances and surface finish on every part! Its surface strength is high and smooth, POM has excellent sliding and wear resistance Advantage : High stiffness , reducing noise from the door Hold the doors tightly onto the chassis, increasing rigidity. Its surface strength is high and smooth, POM has excellent sliding and wear resistance; Good sliding performance , High impact strength even at low temperatures; more durable During initial installation you can choose how tightly your doors will shut, depending on the cars use. you can adjust these bushings to the exact stiffness you prefer. These parts are CNC machined in-house from a solid billet of POM plastic. Our bushings are 16mm thick, for maximum support of the door, and increased longevity compared to thinner bushings, as all forces and friction are distributed over a larger surface area. Easy installion: Remove the old original door bushings with a screwdriver,and install the new door bushings.(Please note,you need to keep the original screwsYou can install by yourself, Save money Package include: 2pcs Door bushings