Leatt helmets feature category-defining 360° Turbine Technology, the helmet is lined with 360° turbines, which are discs constructed from an energy-absorbing material designed to allow the head to move slightly inside the helmet during a crash reducing rotational, direct, and deflective impact energy. This technology has two key advantages, the reduction of rotational acceleration to the head and brain and the absorption of energy upon impact at concussion level. Comes with FREE Leatt Velocity goggles! The 3.5 is both ECE and DOT certified. If you are looking for the latest Leatt helmet range, with increased ventilation and Leatt's Pro-Fit liner, check out the 7.5, 8.5 and 9.5 models. Features: Injected Polymer Compound shell in three sizes Multi-density impact foam Brain injury reduction technology: Reduces forces associated with concussion Moisture wicking, breathable, anti-odor and washable inner liner Designed to offer great neck brace mobility Visor with breakaway function for rotational reduction in a crash Emergency cheek pad removal 360° Turbine Technology: Reduced peak brain acceleration by up to 30% at impact speeds associated with concussion Reduces peak brain rotational acceleration by up to 40% Certified and tested: DOT+ECE 22.05 or JIS T 8133:2015 Weight: DOT+ECE from 1.270 ± 50g (2.80lbs) Sizing: XS (53-54cm - 20 ¾ - 21 ¼")