This full face helmet is constructed from hard polycarbonate shell with shock-absorption EPS foam to provide maximum protection for your kids.?It Features 14 air vents, vented mouth protection, sun visor, adjustable dial, removable liner and other advantages that bring much fun for your kids. The helmet is also detachable to use as a half-face helmet, very convenient to use. Features: Detachable mouth protection design,easy to convert between full face and half face. Strong PC shell and EPS foam absorb shock and impact. 14 flow vents and vented mouth protection keep your child cool. Visor provides increased shade for your kid"s eyes. Adjustable dial makes the helmet fit head sizes: 50-56cm/19.7-22.0in. 12mm thickness washable liner inside?keeps helmet clean,fresh and odor free. Adjustable strap with chin pad for comfortable fit. Equipped with a 6mm thickness replaceable liner,a chin pad,a head back pad for and two 25mm thickness face pads,provides more safety and convenience. Protects your child while cycling,skateboarding,roller skating. Specifications: Color: Red / Yellow / Grey / Blue / Rose / Dark Blue (optional) Material: PC + EPS Head Circumference: 50 - 56 cm / 19.7 - 22.0 in Weight: Approx. 529.7 g / 18.7 oz Package List: 1* Bike Helmet(with 12mm thickness Liner) 1* Replaceable Liner(6mm?thickness) 1* Replaceable Chin Pad 2* Face Pads?(25mm?thickness) 1* Head?Back Pad