Product details:

Features Advanced Polycarbonate Composite Shell - Lightweight, superior fit, and comfort using advanced CAD technology - Aerodynamic shell with large eye port for greater visibility - Impact absorbing, single-density EPS liner HJ-V7 Sun - Shield Visor System - One-touch integrated smoke-tinted Sun - Shield deploys and retracts quickly and easily - Adjustable to three positions ACS Advanced Channeling Ventilation System - ACS Advanced Channeling Ventilation System provides flow-through ventilation - Multi-stage intake vents and exhaust vents allow full front to back fresh airflow that flushes heat and humidity out of the helmet Super - Cool Interior - Moisture-wicking and odor-free interior with advanced Super - Cool antibacterial fabric - Comfortable, removable, and washable - Grooved interior in the temple area for riders who wear glasses HJ-17R Shield and Quick - Slide Shield Replacement SystemQuickSlide shield replacement system allows for quick, secure, and tool-less shield removal and installation - Optically-correct face shield offers 95% UV protection Nylon Strap Retention System - Neatly secures chin strap - Dual D-ring chin strap fastener Technical Information - Standards: DOT-218Construction: Injection-molded polycarbonate thermoplastic - Weight: 3.2 lbs / 1450 grams (approx, based on Size Medium Solid Color)Sizing Wrap a tape measure horizontally around your forehead. Select the helmet that is the closest fit to that size. A helmet should fit snug on your head. If it moves while wearing, it is too large. If it is painful to wear, it is too small. Size Chart - Size CM:Hat SizeInchesXS53-546 5/8 - 6 3/420 7/8 - 21 1/4S 55-566 7/8 - 721 5/8 - 22M