Constructed with a premium formula 1 urethane that offers a hardness profile that's ideal for high-speed indoor play with maximum grip and durability. Perfect for sport court, wood, and smooth concrete. Standard hub wheel designed for the standard 608 bearing size. Tapered wheel profile for speed and agility. Hardness: 76A indoor which is ideal for skaters that are 210 lbs and below. Sizes: 59mm, 68mm, 72mm, 76mm & 80mm.