Pro Fast Rear Wheel Spacers. Constructed from 7075-T6 aluminum with a unique taper design to allow for quicker wheel changes without the spacer dropping out. Also covers full seal to prevent dirt and mud build up. Color anodized to increase durability, which helps to reduce surface wear and lessens the amount of dirt entering the hub which in turn extends the life of the bearing. Features: 7075-T6 aluminum construction. Taper design. Color anodized for durability. Laser-etched logo. Sold as a set.