MOON Road and Mountain Bike MTB Helmet, Light Weight with High Grade EPS and PC Material: High grade Expandable Polystyrene (EPS) and Polycarbonate (PC); Certified by CE EN1078 and CPSC Design: The design details consists of high grade double-sided velvet pads Size and Weight: Medium; 55cm - 58cm, 21.65" - 22.83" having a weight of 230g and an adjustable screw to help with a precise fit Additional Information: The high density EPS foam makes you feel more comfortable by generating cushioning effect. There are 25 air vents which allows enhanced air flow making riding cooler. The Snap-on visor for protection is removable making the helmet suitable for road and mountain bikes