This is the JBL PAIR Replacement Foot Pockets for Long Blade Fins Features: Ideal for free-diving/spearfishing Comfortable fit and effortless propulsion Weight of the pair is 2 pounds It all starts with the foot pocket, and the JBL pockets are engineered for comfort and optimum transfer of energy providing divers with effortless propulsion. JBL has combined two thermo rubber stiffness compounds: one for comfort, and the other for strength. The end result is limited foot fatigue and unmatched power. The blade is constructed of thermoplastic polymer and is set at a 22 degree angle following the natural foot to leg geometry. Side rails offer additional stiffness and prevent water spilling," channeling all power to thrust.