Self-adjusting fin straps are one of the best ways to don and doff your fins. It also makes it easier to use different size booties. Steel spring straps are a relatively new product for fins. It was invented by cave divers that didn’t want their rubber straps breaking on them in the middle of a cave. So, they took screen door springs and made fin straps out of them. Typical rubber straps have a good chance of breaking at some point. If you are lucky, it will happen as you are putting them on before a dive, not in the middle of one. While you should always try and carry a spare strap on you, replacing a strap can be a pain in the middle of a dive.
The spring strap helps avoid most of these problems. Available for many open heel fins, spring straps permanently mount to the fin. Furthermore, spring straps typically attach using rust-resistant metal hardware. SCUBAPRO Steel Spring Straps are available for SCUBAPRO Jet fins, Twin Jet Max, Veloce fins, and the Seawing Nova fins. They are made with High-grade marine steel. These straps can replace the traditional fin strap with the added benefits of being easier to don and doff, and they will compensate at depth for the pressure underwater. The flexible nature of the spring strap tightens as you descend to compensate for the crush on your boots, meaning your fins stay on at the exact tension you set them to at the surface.
Spring straps are strong springs with a rubber or nylon heel cover for comfort. Instead of having to adjust the tension every time you put them on like with traditional straps, you simply stretch the spring over your heel.
This decreases your time and energy spent putting on and taking off your fins before and after a dive. Several models of fins now come with spring straps pre-installed, but they can also be added to many fin models.
The other type of self-adjusting straps is made from quality marine-grade bungee designed for years of reliable use. Marine grade bungee is design and construction, making it ideal for prolonged exposure to moisture, sunlight/UV radiation, and the general wear and tear that fins regularly go through. A denier Dacron polyester cover is thick and long-lasting, repelling water and resisting abrasion better than nylon. Made from a top-quality first extruded latex rubber, this bungee has a consistent 100% stretch and high modulus that won’t lose its elasticity as many others do. Bungee straps are depth compensating as they compress when your neoprene boots get thinner due to increased water pressure. Like the steel spring, the bungee is self-adjusting at depth. Upon ascent, they decompress keeping fin straps comfortable throughout the dive. Straps have a large rubber finger loop to aid in donning and doffing. Marine bungee is highly reliable and has a very low percentage of breaking. All this being said, I know you can break it if you “test it” to try and prove me wrong.