High impact-resistant ABS helmet features ventilation holes, rain gutter, durable stainless steel mesh visor, strong flip up and down function, detachable sun peak, articulated cap-mounted ear cups and height-adjustable ear muffs. NRR value is 23 dB. "Air Flow Control" technology for optimum and consistent noise attenuation and enhanced communication. Snap-in comfortable ear cushions and ratcheting adjustment harness. Fits head of size 20 to 24-1/2 in (50 to 62 cm). Snug-fit harness and highly absorbent sweatband.