Product name: Integrated bicycle riding helmet Model WX-016, adult helmet, both male and female. Size L/One size fits all, with a head circumference of 54-63cm, a head width of 18cm, and a head length of 22cm. It has an adjustable knob to adjust the size of the head circumference. Material Brand new EPS foam+PC sheet integrated molding/built-in lining/nylon webbing and nylon material adjuster. Inner cushion: The inner cushion is a double-sided velvet lining strip, with several colors and styles, subject to the actual item received. Features: The 18 hole design is more reasonable, with a beautiful and fashionable design. The hole position design is reasonable, breathable, and convenient to wear Wind tunnel and duct design effectively reduce wind resistance.