C4 Carbon - 0.5 mm Open Heel Socks mask Choose your normal EU shoe-size

Choose your normal EU shoe-size range: S for 35–38

or if pulling an unconscious diver back to the surface in case of emergency

2x balloons

Sequential Frenzel and Mouthfill training

C4 Carbon - 0.5 mm Open Heel Socks mask Choose your normal EU shoe-sizeC4 Carbon 0. 5 mm Open Heel Socks The C4 Carbon 0. 5 mm Open Heel Socks are ultra thin neoprene socks designed for freediving foot pockets. They add a light protective layer between your foot and the fin without significantly changing the fit. Use them when your fins already fit well, but you want less rubbing, fewer pressure points and more comfort during pool training, depth sessions or long open water dives. The 0. 5 mm thickness is the key point: