Lazer Bullet 2.0 cycling helmet The Bullet 2.0 provides the answer to the dilemma between ventilation and aerodynamics. Thanks to its narrow shape and closed shell, the helmet is extremely aerodynamic, but a quick adjustment of the Airslide system ensures sufficient ventilation. With its adjustability, this road bike helmet is the perfect helmet for all your rides. Even in the closed position, the sides, back and top of the Venturi cap in combination with the internal ventilation channels ensure that air always flows through the helmet. In addition, the Bullet 2.0 allows for a quick and easy installation of the LifeBEAM technology, which allows you to measure your heart rate. Specifications: Model: Bullet 2.0 LifeBEAM Color: Black Gender: Unisex Outer shell material: Plastic Intermediate shell material: Foam Inner shell material: Mesh Ventilation: 8 ventilation openings + Airslide system Weight: 315 grams Construction: In-Mold Adjustment system: ATS Safety certificate: CE-CPSC-AS Head circumference: 52 - 56 cm Size: S