Our Onsen 4/3 is the one-suit quiver killer. The geometric cell structure of Yamamoto #40 in our Onsen wetsuits are 98% water impermeable and locks in body heat, which allows this 4/3 exceptionally comfort and warmth into water temps that could warrant a 5/4. Onsen wetsuits are constructed with 100% Yamamoto #40 neoprene. Every detail has been tested in the harshest of conditions and designed utilizing comprehensive research and development that implements environmentally sustainable materials. Water Temp: 50°F to 57°F | 10°C to 14°C Model Size: Model is 6’0” tall, 185lbs and is wearing a size Large Product Features Yamamoto #40 neoprene Front-zip entry Abrasive resistance knee pads Glide neck skin Thermal lock fleece lining Glued and blind-stitched taped-sealed seams Tapered & matrix-dot wrist grip Ankle drain holes Key FeaturesYamamoto #40 neopreneThe Global Leader in sustainable limestone-based neoprene.Sustainable, Maximum Flexibility, Higher Memory Value, No Chemicals.Glued and blind-stitched taped-sealed seamsTriple threat performance to keep water out and reduce chafing in seamed areas.Thermal lock fleece liningPlush and quick drying this fleece lining keeps you warm in the harshest conditions.Front-zip entryOffers easy entry and flush resistance.Meer tonenMinder tonen