509 Mach IV Modular HelmetThis completely modular helmet features iconic 509 graphics in an aerodynamic design, making it easy to converse with your riding partner, cool down at stoplights, or enjoy a sip of coffee during your morning commute. With adjustable ventilation in both the top and chin bar, along with a convenient drop-down sunshade, this helmet is sure to become your go-to choice for everyday commuting.Features: Intermediate oval Full-face modular helmet functionality Aerodynamic injection molded shell design 2-setting adjustable chin bar venting provides adjustable airflow control while riding Top helmet adjustable air vents Interior drop-down sun shade Multiple shield options available DOT Certified