Need some thin impact-protective armour when riding or racing Patented technology is woven into the Troy Lee Designs UPV 3900-HW vest, with a wide neck opening for comfort, the anatomical design has integrated protection zones, and dense Strata-Foam guards the spine and other key areas of the back. Created as an ideal hot-weather base, the Vent-Trak moves air through flexible channels to cool your skin, and Hex-Mesh disperses impacts with dimensional mesh construction, while allowing air to flow freely.