Less Drag, More Thrust, Less Strength is Used Latest Technology in Composite Plastic Polymer Materials Light Fin (Great Travel Fin) Increases Thrust and Reduces Fatigue Flexibility and Rigidity for Efficient Propulsion Less Air Consumption Power Rails: Backbone of the Split Fin, Highly-Resilient, Storing and Releasing Energy with Every Kick Semi-Ridged Flex Battens: Control the Precise Wing Shape to Optimize Thrust and Reduce Drag Large Surface Area Blade Improves Pivoting, Turning and Alternate Kick Styles Thin, Yet Strong and Highly Flexible Hinge Points Cause Blade to React Quick-and-Efficiently Anatomically Contoured Foot Pocket Designed to Fit Foot without Stress Points Soft, Comfortable Full Foot Pocket Foot Pocket: Large Heel Pull-Tab for Easy Donning and Doffing of Fins Sizes US: 4.5-5.5, 6-7, 7.5-8.5, 9-10, 10.5-11.5 and 12-14 Colors: Black or Yellow Split fins have become the most popular style fin in diving today. Just look around when you are out beach diving or on the charter boat and you will soon discover that more divers are making the switch to this style fin. Why are they so popular? They are popular because they work, and you, work less! A split fin performs more like the combination of a whale's tail and a propeller. When you kick the two separate blades twist and create more of a propeller surface which will increase your propulsion and lift. You feel as if the fin is not strong enough to keep you moving as fast as you are accustomed with your full bladed fin, yet you cover the same distance in the same time.