EZ Gains products are designed, manufactured and tested in the UK and conform to safety regulation. This product has been wind tunnel tested at (Silverstone Sports Engineering Hub) and is as fast as a top end disc wheel. The EZ Disc has all the aero benefits of the EZ Disc SL, it's just 1/3 heavier on average around 150-200g and takes less than 15 minutes to fit. Aerodynamic rear disc wheel covers for road racing bicycles. Turn your wheel into a disc wheel and enjoy meaningful performance gains. Custom engineered to fit all makes and models of wheels, brakes, and rim depth options. Save 2-3 Minutes over 90k by adding an EZ Disc to your wheel, regardless if the course is hilly or not, proven to be more stable in the wind. Check out our science page. (Patent Authorise) BTF-CTT Legal / ITU - ETU / Ironman Legal / World Triathlon ISO Accredited. Ironman Triathlon and World Triathlon have confirmed the EZ Disc is legal to use in draft–illegal races and conforms to safety standards set out by governing bodies 5.03 Ironman (World Triathlon) (h) All aspects of the bicycle must be safe to the rider and to other athletes in the Race. Minimum safety standards include, but are not limited to, meeting or exceeding the standards of a reputable safety standards organization (such as CPSC, ISO, or other equally reputable safety standards organizations)