This package includes 1 set of wheels (4wheels) and 8 bearings. Spitfire Wheels Formula Four. 99A Durometer, 57mm. Lock-Ins Shape. Asymmetrical shape and design featuring a conical cut profile opposite a straight edge side. Lock on in. Amp bearings are the epitome of durability and speed. These high-quality ABEC 5 bearings are strong enough, fast enough, and more than resilient enough to help you carve or cruise your own path. With a thermally applied coating to enhance corrosion resistance and hardened steel balls for a higher Rockwell rating, these bearings will ensure long-lasting durability to keep you rolling. Including fritcion-free rubber shields pre-lubricated with Amp Synthetic Speed Oil.