FX-4 helmet by Zamp Racing. The FX-4 is packed with features and is an excellent choice for racers on dirt bikes, ATVs, and more. Each FX-4 helmet is lightweight and aerodynamic, and features a removable liner for easy cleaning. In addition, features include: Lightweight composite fiberglass shell Adjustable exterior air vents on chin and scalp areas Easy cinch strap for quick on and off Each FX-4 helmet meets or exceeds ECE 22.05 and DOT certifications. Sizing Your Zamp Helmet The FS-9 helmet is available in sizes X-Small to 2XL. Like many helmet brands, Zamp determines the size of their helmets based upon a driver's 'hat size,' the circumference around the head just above the ears, and along the top of the brow. For more on helmet sizing, consult the sizing chart below, or in the image gallery:
