1. WITH ADJUSTABLE STRAPS Dive deeper with the adult swim fins. Thanks to the adjustable ankle straps, adult users size 40 44 can easily find the perfect degree of tightness for maximum comfort performance. 2. High speed swimmingEnjoy the pleasure of high speed swimming with our swim fins, which are designed with liquid mechanics to reduce resistance underwater, simplify the design to improve efficiency, and transform your kicks into stronger drive, so you can swim in the water with ease. 3. Ergonomic design: with their stable, not tight fit, our flippers are perfect for adult swimmers, providing maximum comfort and reducing strain on the legs even during prolonged swimming, thanks to their lightweight, high quality material. 4. Easy to carry and convenient to store: These flippers are compact in design, do not take up space, making them easy to store in hand luggage and easily transported to any diving destination, so you can start an adventure effortlessly.