The Royal Assassin wheel is a combination of cutting edge hub design with old school urethane production. Due to the time consuming nature of producing these wheels, we will only be producing 10 sets per week maximum. Application: Indoor Size: 59mm x 38mm Urethane Colour: Gold Hub - Black Urethane, Silver Hub - Blue Urethane, Silver Hub - Red Urethane Hardness: 88A, 92A, 95A Made in Australia Royal Assassin wheels only accept 167 or 688 bearings to save weight. They will not fit 608 bearings. If you use 7mm axles on your plates, choose the 167 bearings. If you use 8mm axles on your plates, choose the 688 bearings.