The Eleiko XF Bumpers composition enhances durability and delivers an incredibly long-lasting disc designed for tough training and varied environments. The design updates include a more narrow 45 lbs disc, one that matches the width of the 35 lb discs, so more weight can be loaded on the barbell. The 10 lb and 15 lb discs are designed with a smaller 320 mm diameter and thicker width so bumpers won't warp and break. Our compressed recycled crumb rubber is soft yet durable providing fantastic sound dampening and shock absorption. Discs are sold individually.