Add a new dimension to your home or garage gym fitness equipment set up. Bumper plates are Olympic-sized weight plates that are made of thick, high-density rubber for the purpose of allowing a loaded bar to be safely dropped without risk of damaging your lifting platform, the plates themselves, or the floor. Ideal Uses General strength training Olympic weightlifting Sport Specific workout (Baseball, Basketball, Football, Wrestling, and Martial Arts)Specifically, our black bumper plates are made from 100% virgin rubber. We used virgin rubber to help reduce the bounce of the weights, which lowers the chances of injury. The plates are finished with a semi-gloss layer that will help extend the lifetime of your bumper plates. The stainless steel collar or inserts will fit on most Olympic style 2” barbells. Furthermore, the collar is designed with a lubricated surface, so that the weights will stay in place when performing weightlifting exercises. Specifics Collar diameter – 2”Weight Plate diameter - 17.75"*** NOTE - 10 lb plates and 15 lb plates are NOT designed to be used ALONE. The 10 lb and 15 lb weight plates are thinner and are meant to be used in conjunction with the larger weight plates to prevent bending on the 10 and 15 lb plates. Otherwise, you may incur damage if used alone. ***