Waterproof H1 Polar Evoluted High Visibility Bibed 5 10mm Hood Size:Extra Large this session helps you understand Option:Non Regulated this session helps you understand your options before making the jump like those in climbing or skydiving H1 5 10mm HVH includes the unique HAVS (Hood Air Venting System) which uses one way valves to vent annoying air build up in the hood The Waterproof H1 High Visibility Hood features a high visibility orange coloured surface with reflective patches for ultimate visibility and detection in choppy sea conditions in addition to the standard 10mm double layered protection in critical heat loss areas and glide skin seals for the neck and face