O'Neill Psychofreak Men's Wetsuit 4/3mm ZEN Zip SSW - Best Seller neoprene TechnoButter 2 Firewall neoprene in the body & legs TechnoButter 2 AIR Firewall neoprene in the chest & back panels Double SuperSeam Weld (Watertight Stitchless Technology) Super Seal Cuffs Patented Z.E.N. Zip Closure System with Drainhole