If you've got open heel fins, you'll need to choose between a buckle strap or a bungee strap. Both do the same job — holding the fin on your foot — but they suit different divers.
Buckle straps
The traditional setup: a strap that threads through a buckle so you can dial in the exact tension. Buckle straps give you the most precise, fully adjustable fit, which matters if you're sharing fins between people with different foot sizes or wearing different thickness boots depending on the season. The trade-off is they're fiddlier to get on with cold, wet hands, and the buckle is one more thing that can wear out or snap. The Cressi Fin Strap is a straightforward replacement if yours wears out.
Bungee straps
A bungee (or spring) strap replaces the buckle with a stretchy loop that you simply slip your booted foot into. Once it's set up, the fin goes on and off in seconds with consistent, even tension every time — no re-adjusting, no fumbling with a buckle at the surface in a current. It's a popular upgrade for divers who've settled on one boot thickness and want convenience over fine-tuning, like the Mares Bungee Strap (Pair).
Which is right for you
New divers or anyone still figuring out their ideal fit are usually better starting with a buckle strap. Once you know your setup, switching to bungee is a cheap, quick upgrade that most divers don't go back from.
Browse our Scuba Diving Fins range, or check Scuba Diving Accessories for replacement bungee kits.