Wilwood’s ProStreet / ProSpindle Hub Wheel Stud Kits contain 5, 10 or 12 quantity high strength alloy studs for standard Pro Street and Drag Hubs. Studs (dependent on length) can have a Hex Socket head or 12 point head an 1/2-20 thread size and are available in 3 lengths With strengthened caliper mounts allow for better geometry and clearance with specific designed brake kits that utilize 12.19" to 15.00" rotors.