Ivation Adult Swim Fins - Diving Fins - Adjustable Speed Fins, Super-Soft, for Diving,Snorkeling, Swimming & Watersports Speed-Focused Fins Feature Long Sole Plate for Added Thrust & Foot Strain Relief Adjustable Strap System Easily Slips On & Off with Simplified One-Handed Motion Contoured Foot Opening Offers Improved, Lasting Comfort Even Without Booties Pro-Grade Polypropylene Construction Ensures Efficient Energy Transfer from Kick Rotating Smooth-Action Hinge Post Keeps Fin Perfectly Angled Throughout Cycle