Disc brake mount adaptor reduces brake disc wear and is suitable for bicycle disc brake systems with a diameter of 180mm. Bike disc brake adapter is made of 7075 aluminum alloy and professional designs to insure the great fit and correct operation. Brake caliper mount adapter is simple installation, tightening the screws directly to ensure they are firm, great compatibility and high reliability. CNC precise turning and eccentric screw hole design. T6 hard processing, advanced anodic oxidation technology. And it can help improve the overall performance. Package includes 2pcs bike disc brake adapters, 4pcs bolts and 8pcs washers , which can completely meet your daily use needs and replacement. Material Aluminium Alloy Colour Black Bolt .