Olympic Plates Our Olympic plates are available in cast, rubber and urethane. GPI plates have three holes that are positioned in a way that allows the user to use the plate in a safe and easy manner. Our plates are made of the finest cast iron, rubber and urethane available creating durability and strength. Available in 2.5lb., 5lb., 10lb., 25lb., 35lb., and 45lb. sizes. Cast Iron - High-grade cast iron with a baked Hammertone chip resistant finish, plate back, edges and hole are precision machined for an attractive appearance and fit. Rubber - Precision castings, machined holes, top quality virgin rubber materials, formulated and tested for longevity. No recycled rubber is used. Urethane- Our urethane has been tested for durability and wear. Plates are colored in the International Color Scheme.