Features:Professional Protection,Save Your Life: High-density PC case with great technology will surely improve safe performance that it can save your life in emergent situation.Bike Helmet with Light,Safe and Protective: This helmet comes with light which helps people behind you clearly recognized your direction.Super Comfortable:Bicycle helmet in special aerodynamic design super lightweight no more burden; 21 breathable vents effectively reduce air resistance and reduce sweating.Adjustable Size:Adjusting knob at the back of the adult helmet helps to adjust the head circumference. Adjustable Size: 54cm-61cm meet the needs of most people.Removable Lining:Removable liner pads make it easy to clean and keep fresh smelling helmet and keep bugs out of your hair.Notice:Actual color may be slightly different from the image due to different monitor and light effectPlease allow 1-3cm deviation due to manual measurementSpecification:Material:PCHead circumference: 54-61cmincludes:1x Bike Helmet