For 39mm fork tubes. Black anodized aluminum. Direct replacement for the stock fork tube plugs and cap bolts. Allows tuning the front suspension to suit weight and riding style. Offers a 20mm adjustment range, using an Allen head (hex key) wrench. Easy installation. / Fitment: 39mm fork tube models: 87-94 FXR; 91-05 Dyna (Excl. FXDWG); 88-15 XL Sportster & 16-21 XL Sportster cartridge models right cap only. (Excl. 97-03 1200S; 16-21 1200X Forty Eight; 16-up 1200CX Roadster); 16-20 XL1200T L&R caps