This is a fantastic pair of Hollis F2 Scuba Diving Open Heel Light Weight Fins with Spring Straps Features of these wonderful fins include: High grade, heavy duty monoprene construction Angled strap mounts for comfort and a better transition of power Spring heel straps w/ easy-grip heel tab Multiple strap mounting positions for a fine tuned fit Vented blade to reduce stress while accelerating water over the blade Generous foot pocket with 3 sizes - Small, Regular and XL Increase your power to weight ratio with our new F2 fins. If you are a traveling diver, looking to reduce weight or just favor a lightweight fin, look no further. The patented F2 is designed to add blade surface on both the downstroke and upstroke to increase your efficiency with any type of kick. The F2 is injection molded using monoprene and uses a shorter blade design which packs easy and improves agility in tight areas. Standard with adjustable stainless steel spring straps.