A sweet blend of classic Pro-tec styling and modern protection EPS liner technology, the B2 destroys all others in fit and style. Timeless flare and three different ABS shell sizes make the B2s fit unrivaled. The perfect blend of proven performance and style. The B2 Bike Pro-tec helmet is taken from the Classic Pro-tec design and equipped it with a High-Impact ABS Shell and Multi-Impact SXP lining. The B2 Bike helmet has 15 open vents for extra ventilation. The shell is high-impact ABS, with the Multi-Impact SXP liner and an interior of die-cut PU foam padding with laminated Nylex. The Krown Action Tri-pack is designed to take abuse from all types of action sports including skateboarding, bmxing, and inline skating. Includes KROWN Knee Pads, Elbow Pads, and Wrist Guards. See below for sizing instructions on the wrist/elbow/knee pads. To ensure a good wrist guard fit, measure hand circumference at the knuckles and match to the sizes listed: XS 7.0 – 7.5 inches. To ensure a good knee pad fit, measure the circumference of your extended knee and match to the sizes listed: XS 10 - 13 inches. To ensure a good elbow pad fit, measure the circumference of your elbow with your arm outstretched and match to the sizes listed: XS 4 - 6 inches.