Wilwood 120 15564 SI Wilwood Caliper Billet Narrow Dynalite Radial Mount 3.00in Piston 1.00in Disc Pin on Cougars. Wilwood 120 15564 SI Wilwood Caliper Billet Narrow Dynalite Radial Mount 3. 00in Piston 1. 00in Disc Wilwood's venerable DynaLite calipers are used in all forms of racing, and the latest Billet Narrow Dynalite Radial Mount (NDLR) series are better than ever. Starting at just 3. 20 pounds, this compact and lightweight caliper now incorporates a more rigid radial mount design. Engineered with a spacer less body specifically for . 38, . 810 and 1. 00" width rotors and a center bridge bolt adding to overall caliper strength and positive retention of the top loaded pads. A durable aluminum oxide ceramic Mil Spec Type III hard anodized finish further enhances the durability of the caliper by resisting bore wear and surface abrasion. Billet NDLR calipers can be directly mounted over studs on a 4. 75" center, or used with a radial mount bracket kit in place of a tab mount caliper. Internal damping springs, internal fluid crossover, controlled retraction in bore seals, and 3 8 cross bolts for added strength and rigidity all adds up to consistent pedal feel from start to finish. Uses type 7816 brake pads with many Wilwood compound options to fine tune your driving style and track conditions.