Mares Avanti Superchannel Open Heel Dive Fin

Open-heel fins have an adjustable heel strap and are worn with dive boots, which protect your feet on shore entries and add warmth. Full-foot fins slip on like a shoe against bare skin or a thin sock, and are typically lighter and easier to pack. Most scuba divers choose open-heel fins with boots, while full-foot fins suit warm water, snorkeling, and pool use.

Open-heel fins should be sized around the boots you will actually wear, snug with the strap set so your heel stays seated and your foot does not slide forward in the pocket. Full-foot fins should fit like a firm shoe, with no heel lift, no pinched toes, and no gap that lets water pump in and out. Too loose causes heel blisters and lost fins in current, and too tight causes foot cramps.

Choose your boots first and size open-heel fins around them, because sole thickness changes the foot-pocket size you need. A thin warm-water boot and a thick cold-water boot with a rugged sole can easily be a fin size apart. If you already own fins, bring them along when you buy boots so you can check the combination.

Spring straps replace the adjustable rubber strap with a stainless spring that stretches on and off, so there is nothing to buckle with cold or gloved hands and no rubber strap to perish and snap mid-dive. They hold constant tension, which many divers find more comfortable and consistent. They are sized rather than adjustable, so match the length to your foot pocket and the boots you dive.

For travel, length and weight matter most, so shorter blades and travel-specific open-heel or full-foot models pack more easily and save baggage allowance. Some fins have removable blades or compact foot pockets designed for luggage. Pack fins along the outside walls of your bag, where they also act as protection for softer gear.

Paddle fins use a solid blade that transfers power directly, which many divers prefer for precision, control in current, and non-flutter kicks such as the frog kick. Split fins have a slit down the blade that lets water pass through, which generally makes flutter kicking easier on the legs but gives up some control and works less well with other kick styles. Neither is inherently better, so let your kick style, leg strength, and conditions decide, and try both if you get the chance.

Rinse them in fresh water after each dive day, paying attention to buckles, springs, and strap channels where salt collects, and dry them out of direct sunlight. Store them flat or hanging from the foot pocket rather than standing on the blade tips, which can take a permanent bend. Check straps, buckles, and any screws before every trip, since a failed buckle is the most common fin problem.

Channel Thrust Technology is Mares' blade design, inspired by marine mammals, that delivers more power and efficiency with less effort per kick. On the Avanti Superchannel the blade uses three channels that let it arch during the fin stroke while water is channeled in the opposite direction of motion, which minimizes thrust loss and turns more of your leg effort into forward propulsion.

It is offered in three sizes: S (Small), REG (Regular) and XL (X-Large). Color options are Royal Yellow, Royal Blue, Black and White Aqua. Because it is an open heel fin worn over dive boots, choose the size around the boot sole thickness you actually dive. If you are between sizes, call 888-701-4017 and we can talk through your boots.

This version of the Avanti Superchannel OH uses a bungee strap with an ergonomic heel pad. The bungee stretches over your heel so there is nothing to buckle, which makes donning and doffing quick and easy with cold or gloved hands, and the heel pad adds a flexible, comfortable fit against the back of your boot.

In size R the blade measures 37 cm / 14.6 in with a blade thrust area of 730 cm² / 113.1 in², and a single fin weighs 0.9 kg / 2 lb. Blade length varies from roughly 35 to 37 cm depending on the size you choose, so smaller sizes are slightly shorter. The blade is built from thermoplastic rubber and Tecralene.