HB-103SV 10 Ventilation Channels for Cooling Comfort Lightweight High Strength Polypropylene Straps Quick Release Buckles Snell B-95A Certified CE and CPSC Standards Size :S/M,L/XL INCHES:　22~23.5,23.5~25 CM :56~60cm,60~64cm Color :Silk-Screen Vent :10