Highlights: Inner material:hight density eps(expanded polystyrene) External material: pc shell Technology: in-mold combination of high strength eps create a durable light weight shell Certified by cpsc / ce / t¨¹v-gs / snell / astm / reach- safe and reliable Cam-lock levers for easy strap adjustments Soft sponge inside provides comfortable wearing experience Specification: Best use: biking, cycling Gender: unisex Style: sport Color: pantone Material: eps, pc With detachable sunvisor: no Size head circumference (inch): s/m(20.5-22); m/l(21-23); l/xl(23-24.5) (cm): s/m(52-56); m/l(54-58); l/xl(58-62) Vents:31 Net weight: 280g Color box packing;net weight: 250g;size: 28.5*16*22.5cm