The all-new S-M5 helmet is the result of more than five years of intensive study, development and testing. Alpinestars scrutinized every possible aspect to engineer… • Lightweight outer shell is constructed from a technologically advanced impact resistant thermoplastic in two sizes. • The inner and outer surfaces are engineered to minimize the effects of oblique impacts. • Multiple density inner liner to ensure the correct density in the correct area for enhanced impact absorption. • Side shell