O'Neill Wetsuits - O'Neill Psycho 3 5/4mm Zen Back Zip Wetsuit - Black/ Black/ Black :: Men > Wetsuits. Pocket: External key pocket with integrated loopDouble Super Seal Neck: Fully water tight to keep you warm and dryZ.E.N. Zip Entry: Patented technology featuring a pullover neck seal and integrated drainage holeDouble SuperSeam Weld: Silicone-based urethane seal to both sides of triple glued seam - stitchless. thinner & lighterTechnobutter 2-Air Firewall: Lightweight. super warm chest panel lined with a moisture-wicking insulating jerseyTechnobutter 2 Neoprene: Super stretch neoprene - 20% lighter. 30% less water absorption. quick drying propertiesContortionist Shoulder Seams: Superb flexibility where you need it most - lets you paddle with total easeSeamless Paddle Zones: Strategically placed. anatomically shaped panels for more efficient movement & rash eliminationKrypto Knee Pads: Ergonomically shaped pads provide durable protection for you and your boardSuper Seal Wrist Cuffs: Fused to create a very low profile Size: SMALL TALL.