Designed for optimum safety, the 4S helmet features 4 layers for successive shock absorption and improved resistance to lateral compression.The 4S breakdown:- 1S: outer shell designed to absorb the first part of impacts. It is made of an absorbent polymer and designed to deform under impact.- 2S: in the event of an impact, this interface, made from an elastomer developed for Formula 1 racing, absorbs the energy of the impact to absorb it.- 3S: the main shell, reinforced with fiberglass, provides rigidity and protection. The impact is already cushioned when it reaches this level.- 4S: the EPS skullcap decelerates the impact by crushing under the pressure of the impact, protecting the skull and minimizing the risk of head injuries.- EXTERNAL SHIELD: injection-molded in thermo-composite resin to limit the risk of perforation. Thanks to its front openings and rear extractors, this helmet offers optimum ventilation.- INSIDE SHIELD: EPS shock-absorbing element in variable-density e...