Borealis Semi Dry Top Level Six USA Borealis Semi Dry Top borealis Borealis Semi Dry Top Level Six USA. The Borealis is a long sleeve semi dry top constructed from our award winning eXhaust 2. 5 ultralight (UL) waterproof breathable nylon. This top is designed to be light, breathable and offers users a full range of motion. The Borealis features our overlapping double tunnel and our new Stealth waist cinch system to work with your skirt and provide you with a dry seal and better paddling experience. Features: YKK aqua guard zipper on chest pocket Double tunnel and Stealth waistband system Adjustable neoprene wrist and neck closures Hidden safe key pocket Exhaust 2. 5 UL waterproof breathable nylon