The Roxy 5/4/3 mm Swell Back-Zip GBS wetsuit is designed for... to keep warm in cold water. It is made from environmentally friendly fabrics which combine flexibility and warmth. Made from mostly recycled materials and Stretchflight Eco neoprene to reduce waste and fossil fuel consumption and of course keep our body warm and keep water out. This wetsuit is equipped with 5/4/3mm thick insulation applied to the body to maximize core warmth and extremity mobility Zip at the back for comfortable paddling and also taped and stitched seams for waterproofness.