Ozone Board Leash Coiled (Ankle Cuff)These leashes are built directly from Ozone and designed to be used with foil boards. Ozone has two options to choose from to suit your personal preference. Some people who are surfers tend to go with the ankle connection because that feels most normal to them. Other riders are choosing to use the calf connection because it moves the leash farther away from the feet which helps prevent getting tangled up in the leash.