RCU Designs has designed a replacement rear shock absorber adjustment knob to replace the plain, plastic unit that comes stock on your BMW. Machined from aircraft-quality, billet, aluminum alloy, the cap is anodized in a clear, satin finish. The inside has four detents machined into the sidewalls to allow exact 1/4 turn adjustment in lieu of the 1/2 turn adjustment available with the stock cap. This is a beautiful piece you will be proud to display on your BMW with the adhesive-backed roundel (included) setting off the top of the plug and hiding the included attachment screw.