Tsar Fitness Olympic Bumper Plates are high quality, high performance, durable, have low bounce and designed to IWF standards, they are built to withstand any punishment you throw at them. Our plates undergo many layers of strict quality control to ensure they meet the IWF's weight tolerances within+-1% of claimed weight, our bumper plates are 450mm in diameter have a 50.4mm collar opening to ensure they fit all Olympic size Barbells.