FEATURES: Plastic/Fiber-reinforced Brake Disc Steel Center Shaft Adapter INCLUDES: One Brake Disc One Center Shaft Adapter REQUIRES: None, item is a stock replacment part. SPECS: Brake Disc Inside diameter: 14.5mm (.57") Brake Disc Outside diameter: 30.5mm (1.2") Brake Disc Thickness: 3.4mm (.134") COMMENTS: Center of Brake disc is "keyed" to keep it stationary when assembled along with the Center Shaft Adapter.