CAP Barbell 2" Muscle Clamp Collars, Set of 2: * Helps improve the safety of your workout conditions * Fit on all Olympic size bars * Prevents weight plates from slipping off * Unique patented design allows for quick placement and removal of the collars * Commercial gym quality * Special plastic resin composition is extremely tough and durable * Set of two Olympic bar collars * Model OC-11 * WARNING: This product contains one or more phthalate chemicals known to the state of California to cause birth defects and other reproductive harm