This wheel was made for those outdoor hockey players that get tired of burning through their wheels so quickly. The worlds best selling outdoor wheel! Created with our abrasion resistant endurance urethane for superior outdoor wear and great grip with a hardness of 85a. This HiLo set includes 2 different sized wheels, 76mm and 80mm. HiLo sets only work on certain skates that take 76mm wheels in the front and 80mm wheels in the back.