O\'Neill Psycho One 4/3 Womens Back Zip Summer Wetsuit in Black The O\'Neill Psycho One 4/3 Women\'s back zip wetsuit is for those that want top performance in terms of warmth and flexibility from there suit. It features Technobutter 3 for unreal flexibility in the water and pretty much feels like your not wearing a wetsuit. If you want a great all year round performance suit than you have found it in the Psycho One 4/3 wetsuit. Anti-Flush Barrier Double Seal Collar 100% TechnoButter 3 Z.E.N ZIP CLOSURE SYSTEM: Patented system with free floating zipper panel and anti-flush barrier-2 with drain hole, keeps you warm and unrestricted. FLUID SEAM WELD: 8mm silcone-based urethane sealed exterior with a triple-glued and blind stitched interior. Watertight, durable, and ultra flexible seam. TECHNOBUTTER 3: Buttery soft premium neoprene stretches like crazy. Technical yarns and a revolutionary foam rubber core make it light & durable with quick-dry properties. MINIMAL SEAM DESIGN: Insance flexibility, fit and durability using a unique design which utilizes larger panels and less seams.