Vulcan Absolute Competition Bumper Plate Sets are manufactured in accordance with IWF specifications and mechanically drop tested 10,000 times. Thinner profile than most competition bumper plates allows more plates on the bar. Raised lettering is coated with indelible ink that will not come off or fade like most competition bumper plates. Discs are glass bead blasted to provide great aesthetic look after multiple uses. Rubber sits approximately 1.25 mm above disc to ensure super tight fit and minimal metal to metal contact between bumper plates. The steel discs of the Vulcan Absolute Bumper Plate are guaranteed not to depart from the plate or spin within the plate for the duration of the warranty.