This pack of 2 black sheep alienation rims are perfect for any BMX bike enthusiast. With 36 spoke holes and a 20 inch wheel size, these rims are compatible with various BMX bikes including old school, flatland, and racing. The rims are made from 6061-t6 alloy and come with a clincher tire type. In addition, it is important to note that these rims may expose you to chemicals including lead, which is known to the State of California to cause cancer and birth defects or other reproductive harm. For more information, please refer to the California Prop 65 Warning. Get ready to ride with confidence and style with these black sheep alienation rims.