These wheels changed HO SLOT CAR RACING . No more sliding thru the curves and quick off the line starts with AJ's Slot Car polished sponge Slicks. These sleek tires are designed for optimum performance .sponge tires are a little hard , need sanding . These wheels are perfect on HO scale TYCOPRO slot cars With their smooth sponge SLICKS and durable Tycopro crown gear , included are 2 wheels , axle, crown gear , jamb nuts, allow for easy customization and personalization. Whether you're a seasoned racer or just starting out, AJ's Slot Car Slicks are sure to take your racing experience to the next level.