Aether MIPS Synthe MIPS Cinder MIPS Syntax MIPS Agilis MIPS FEATURES MIPS Spherical / Progressive Layering / AURA Reinforcing Arch / Nanobead EPS foam / Eyeglass grippers / CoolFit padding Featherweight webbing with Slimline buckle / Ponytail compatible / Aero Mesh Panels / MIPS equipped Compact shape Full Hardbody coverage / Air-FX padding / Ponytail compatible / MIPS equipped Integrated MIPS technology / CoolFit padding / Featherweight webbing with Slimline buckle Integrated MIPS technology / Coolfit padding / Featherweight webbing with Slimline buckle CONSTRUCTION Independent liners with spherical interface / In-Mold construction with progressive layering / Six-piece polycarbonate Hardbody / AURA Reinforcing Arch In-Mold polycarbonate shell with EPS liner/ Thermoformed SL Roll Cage reinforcement In-Mold polycarbonate shell with EPS liner Thermoformed SL Roll Cage reinforcement Full-wrap In-Mold polycarbonate shell with EPS liner Four polycarbonate hardbodies Full-wrap In-Mold polycarbonate shell with EPS liner FIT SYSTEM Roc Loc 5+ Air Roc Loc 5 Air Roc Loc 5 Roc Loc 5 Air MIPS Roc Loc 5.5 MIPS VENTILATION 21 Wind Tunnel vents with internal channeling 26 Wind Tunnel vents with internal channeling 26 Wind Tunnel vents with internal channeling 25 Wind Tunnel vents with internal channeling 32 Wind Tunnel vents with internal channeling SIZES SUPER FIT SIZES: S (20”–21.75” / 51–55cm) - M (21.75”–23.25” / 55–59cm) - L (23.25”–24.75” / 59–63cm) SUPER FIT SIZES: S (20”–21.75” / 51–55cm) - M (21.75”–23.25” / 55–59cm) - L (23.25”–24.75” / 59–63cm) SUPER FIT SIZES: S (20”–21.75” / 51–55cm) - M (21.75”–23.25” / 55–59cm) - L (23.25”–24.75” / 59–63cm) SUPER FIT SIZES: S (20”–21.75” / 51–55cm) - M (21.75”–23.25” / 55–59cm) - L (23.25”–24.75” / 59–63cm) - XL (24”–25.55” / 61–65cm) *(Available in select colors) SUPER FIT SIZES: S (20”–21.75” / 51–55cm) - M (21.75”–23.25” / 55–59cm) - L (23.25”–24.75” / 59–63cm)