The Metal Mutha's offer a CNC machined aluminum core, designed to maximize speed and roll. The metal core eliminates any small side-to-side movement of the bearings which means the perfectly aligned bearings are allowed to operate as they were initially intended. Love Yo Mutha Soy Compound Skateboard Wheel by Dregs offers size, strength, & stability. The Love Yo Mutha formula uses soy oils to offset the use of petroleum product. A quick turning manueverable wheel for controlled cruising. Lowriding for greater stability. Welcome to the new world of Soy-based urethane. Urethanes are traditionally a petroleum based product derived from a natural gas. These wheels however utilize a new technique incorporating oils from soybeans to offset the usage of petroleum. While it doesn't eliminate the need for petroleum based ingredients, it's definitely a step in the right direction. So Love Yo Mutha. Super Smooth - Long-lasting - Won't chunk out - CNC Alumiunum Core