The O'Neill Psycho Tech 5/4+ Chest Zip wetsuit has been a firm favourite for us and for all of you for many years now. The new 2023 model has been updated with Technobutter 4 neoprene to offer even more incredible performance. Featuring recycled materials the new Technobutter 4 range is the next step in O'Neills sustainability journey. We have put Technobutter 4 to the test already and love how warm and stretchy it feels. The reduced drying time comes in very handy when surfing on consecutive days. Key Features plus 0.5mm for additional warmth anti-flush barrier drainholes prevent water from entering the suit minimal seam design recycled materials - TB4, TB4X, TB4 Air Firewall, TB4 Firewall superseal handcuffs Plasma wrist and ankle seals Krypto knee padz double super-seal collar key pocket with loop Construction stitchless glued seams (triple glued) exterior fluid seam weld interior recycled TB3X tape TB4 (recycled material) - arms and shoulders TB4X (recycled material) - entry TB4 Duraskin (SL) Air Firewall (recycled materials) - chest and back TB4 Firewall (recycled materials) - thigh, butt, shins & calves The new Technobutter 4 material explained: TB4: Technobutter 4 builds on the legendary Technobutter 3, the next evolution of the jersey introduces recycled yarns infused with graphene for increased wear strength and heat retention. TB4X: Technobutter 4x goes beyond the gooey and soft feel of TB3x. Recycled graphene fibres line the jersey allowing for incredible stretch with added strength and warmth retention, all with a new look. TB4 Firewall: The all new Technobutter 4 Firewall utilises the recycled graphene fibres at a thicker pile to create a fire hot feedback loop. As the body heat warms the graphene fibres they conduct the heat back into the body.