This is the Deep See Aqua Glide Fin Open Heel Scuba Diving Fins Features: Open Heeled Snorkeling Fin with Adjustable Strap Neoprene Heel Pad for Added Comfort Comfort and Soft Flexible Foot Pocket Use With-or-Without Boots Non-Vented Blade Provides Efficient Water Flow Increase Power and Speed, with Less Effort Molded Flex Zones Cups and Channels Water Focuses Kick Power for Maximum Thrust Composite Design Using Plastic and Rubber Overall Dimensions: (L x W) 22 x 8" (55.9 cm x 20.3 cm), Based on Size 9/12 Great Travel Fin Deep See's Fin Technology gives speed with less effort. This unique open heeled snorkeling fin with adjustable strap, neoprene heel pad, and comfortable foot pocket, allows use with or without a boot. The non-vented blade provides efficient water flow to increase power and speed, with less effort. Fin has a molded flex zones that cups and channel water focusing the kick power for maximum thrust. Fin is a composite design using plastic and rubber. Fins overall dimensions are (L x W) 22" x 8" (55.9 cm x 20.3 cm) based on size 9/12. Fin is available in multiple sizes and colors."