The Box Three Disc Brake Rotor is a Stainless Steel, 6 bolt rotor designed for BMX Race. Utilizing a small size and rounded outside edges for safety is the optimal size for any BMX Race bike. Features: ISO 6 bolt brake/hub interface Rounded outside edges Lightweight Cutouts High quality stainless steel rotor High quality locking steel T-25 rotor bolts included Specifications: Rotor: 140mm Bolts: 6 Material: Stainless Steel Weight: 78 g / 2.7 oz