If you ding your brake rotor, you have no brakes, which is bad enough by itself, but if you're racing it means YOU LOSE! The SCOTTS Shark-fin is 3/8" thick billet 6061 aluminum, 25% thicker than any others on the market. It is the only fin that incorporates the brake caliper carrier as an integral part of the function. This means the axle passes through the shark fin making it virtually indestructible and your brake rotor protected from defeat. This design is 10 times stronger than the "Bolt-On" type fins and it's a beautiful piece of work.