The Specialized Duet Women’s Helmet is a general purpose cycling helmet, equally at home on the commute, road cycling or on a weekend potter around the local lanes. The Duet is really well vented to keep your head cool & comes with the With exceptional cooling & comfort Specialized’s exclusive Hair Port SX fit system that’s tailor-made for a ponytail, . This is a one size fits all helmet that comes with an adjustment dial so you can fine tune it to find the perfect fit. One-size system based on womens head sizing, designed for easy & accurate fit. Ponytail-ready Hair Port SX fit system with micro-adjustable dial for an easy, accurate fit. 4th Dimension Cooling System optimizes ventilation. In-moulded shell improves strength & reduces weight. Tri-Fix web splitter for enhanced comfort & ease of strap adjustments. Reflective webbing & decals for increased visibility in low-light conditions. Patented clip-on visor included.