Bones Street Tech Formula Wheels Decenzo Black Moon 54MM STF - STF wheels are the hottest wheels around! No need to worry about flat spotting your wheels even after a few slides. These are perfect for technical street skating with a slim profile and the Street Tech Formula. Bones measures there wheels in the durometer B scale which is more accurate than the A scale. These have been tested and proven by the Bones team to be some of the best street wheels ever! sold in sets of 4. Features - Diameter: 54mm - Width: 32mm - Hardness: 83B - Formula: STF - Color: Black - Core: No - Surface: Smooth - Sugg. Use: Street