O'Neill Women's Reactor 2mm Short Sleeve Back Zip Spring Wetsuit Strategic Seamless Paddle Zones, Super Seal Collar (Fully Adjustable) Hidden Key Pocket, Flatlock Stitching (Breathable Seam) Ykk Back Zip System, Top Sleeve & Underseam: Fluid FlexNeoprene--very stretchy neoprene Body: Fluid Foam - Oneill's standard Neoprene, Chest/Back: Mesh smooth skin fluid foam Neck: Smoth Skin Fluid Foam (a dry neck seal)