The Pro Light Fins will improve your kicking power while maintaining optimum comfort whether you're planning a scuba diving or snorkeling trip. A combination of polypropylene and soft elastomer create a powerful yet comfortable blade. Full-length side rails help to direct the flow of water and improve thrust. Quick-release strap buckles make the Cressi(R) Adult Pro Light Snorkel & Scuba Fins easy to put on and take off. FEATURES: Lightweight, highly responsive blades Dual-material blade creates a balance between comfort and power using durable polypropylene and soft elastomer Full-length side rails help the fin track naturally in the water using a standard scissor kick and direct water flow, improving thrust Soft elastomer foot pocket is ergonomically shaped for a comfortable fit Blade extends from the top of the foot to increase the surface area Quick-release strap buckles Note: If using for snorkeling, a neoprene boot for fit & comfort is recommended (sold separately) SIZING: XS: Men's 4-6.5 / Women's 5-7.5 S/M: Men's 6.5-8 / Women's 7.5-9 M/L: Men's 8.5-11 / Women's 9.5-12 XL: Men's 11-12 / Women's 12-13 XXL: Men's 12-13 / Women's 13-14