Giro: SWITCH TO ROWDY The Switchblade MIPS was created for hard-charging descents and the demands of elite enduro racing.Every detail is built for the down, from the MIPS system and multiple certifications (CPSC, EN-1078 and ASTM-1952-DH with and without the chinbar) to the P.O.V. Plus visor and Roc Loc Air DH fit system that features a bumper around the dial to prevent accidental adjustments in case your helmet contacts your backpack or neck brace.The chinbar is engineered to help manage impact energies, and is easy to install or remove in seconds.The full-cut style gives this helmet an aggressive look with an added measure of coverage, while the strategic ventilation, including Wind Tunnel ventilation channels behind the cheek pads, provides plenty of cooling power for everyday riding. SPECS- Removable chinbar- P.O.V. Plus™ visor- Spare visor with camera mount- Ionic+™ anti-microbial padding- Certified to CPSC, EN-1078 and ASTM-1952-DH with and without chinbar- Mips® brain protection systemCONSTRUCTION- In-Mold constructionFIT SYSTEM- Roc Loc® Air DHVENTILATION- 20 Vents with internal channeling- Wind Tunnel™ cheek pad ventilationSUPER FIT™ SIZES- S 20”–21.75” / 51–55cm- M 21.75”–23.25” / 55–59cm- L 23.25”–24.75” / 59–63cmCERTIFICATION- Complies with the US CPSC Safety Standard for Bicycle Helmet for Persons Age 5 and Older