The Hi-Impact plates are slightly thicker than the traditional bumper plates (34mm - 98mm). Tested to a higher drop rate they are more durable and provide a more stable lifting platform even with lower weights on the bar. The Gym Gear Hi-Impact Olympic Bumper Plates are designed to withstand repeated dropping making them ideal for use in Olympic lifting, Powerlifting, Crossfit and other heavy duty weightlifting environments. Product Features: Designed for Olympic lifting Vulcanised rubber that will not break/ distort through high impact movements Will not damage Olympic training platforms Stainless steel inner ring allows for effortless loading on and off Olympic bars Tested to 30,000 drops (15,20 & 25kg), 25,000 drops (10kg), 8000 drops (5kg) Diameter(mm): 450MM Inner Diameter: 50.6(+/-0.2MM) Colour: Black with colour fleck Hardness: 65-75 Weight Tolerance: +/-0.3% of claimed weight Available Weights & Thickness: 25kg - 98mm 20kg - 90mm 15kg - 75mm 10kg - 60mm 5kg - 34mm SPECIFICATION: Brand GymGear Usage Home Use, Commercial Use Condition Brand New Warranty 2 Year Warranty