The Primal Strength Urethane Bumper Plates are our highest quality Olympic bumper plates. The Urethane bumper plates have a machined-steel core and every disc is calibrated and tolerance tested to under 5g. The premium Urethane finish ensures the discs are extremely hard-wearing with no bounce. The discs will not scratch, discolour or break and are perfect for Olympic lifting. All Primal Strength Urethane Bumper plates are Olympic colour-coded and meet the 450mm IWF diameter. The bumpers have a 50mm centre hole. As the discs have machined-steel cores and a Urethane finish they are thinner than our coloured bumper discs, allowing users to load a far higher volume of discs to their bar. Bumper plate width: 5kg Grey: 20mm 10kg Green: 40mm 15kg Yellow: 48mm 20kg Blue: 53mm 25kg Red: 58mm The bumpers are aesthetically superb, with raised, Primal Strength logos and large KG/Training markers in white. The range comes colour-coded in: Grey (5kg), Green (10kg), Yellow (15kg), Blue (20kg) and Red (25kg). The Primal Strength Urethane Bumper Plates can be used with any Olympic bar. Whilst the discs are extremely heavy-duty and hard-wearing we recommend the discs are used in a gym or training environment with the correct flooring and aren’t dropped on concrete floors. The 3-year warranty applies to full commercial gyms with rubber flooring and for indoor use only.