If the outer shell is the armor of a motorcycle helmet, then the EPS liner is the hero that makes the ultimate sacrifice. This is the component that actually saves lives, and the science behind it is incredibly sophisticated. Early helmets used a single, uniform density of EPS foam. The problem is that a crash can involve both high-speed and low-speed impacts. A foam that is dense enough for a high-speed crash might be too stiff to properly cushion a lower-speed impact. The solution, which we have mastered at SPIRIT, is the multi-density EPS liner. We strategically mold together multiple pieces of EPS foam with different densities. A denser foam might be used in the crown, which is a likely high-impact zone, while a softer, more forgiving foam is used in the sides. This allows the liner to manage a much wider range of impact energies effectively. It's a complex and expensive manufacturing process, but when it comes to a motorcycle helmet, it is the only way to provide the most advanced protection possible.