You’ve Probably Seen FINIS SlipFin Pro: Here’s What Makes It Different!
By now, there’s a good chance you’ve seen or heard of the FINIS SlipFin Pro.
The strapless training fin has been making its way onto pool decks, social media, and into the hands of swimmers and coaches over the past year. But while its unusual design is usually the first thing people notice, the idea behind SlipFin Pro goes beyond simply removing the heel strap.
FINIS developed SlipFin Pro around a simple question: can a fin add useful propulsion without dramatically changing the way a swimmer naturally kicks?
At first glance, the biggest difference is what is missing. There is no heel cup and there are no straps. FINIS SlipFin Pro slips over the front half of the foot, leaving the heel and ankle completely free.
That simple change creates a very different experience in the water.
Why Rethink the Traditional Fin?
Swimmers have trained with fins for decades because they work. They can increase speed, improve body position, build confidence and allow athletes to experience speeds they may not yet be able to reach on their own.
But different fins also create different training environments.
Some traditional fins add enough weight or resistance to slow kick tempo. Others provide a high level of propulsion, which can be valuable for strength and overload work but may not always replicate the rhythm a swimmer uses when racing.
That doesn’t make one approach better than another. It simply means different fins can be useful for different training goals.
FINIS SlipFin Pro was developed for the moments when the goal is added speed and assistance while keeping the swimmer’s kick closer to its natural rhythm.
Because the fin is lightweight and leaves the heel exposed, swimmers can maintain a quicker cadence and move more freely through the ankle. The propulsion is noticeable, but it is not intended to overpower the stroke.
For competitive swimmers, that distinction can matter.
Race-pace training is not just about moving fast. It is about learning how the kick, hips, arms and body line work together at speed. If one part of that rhythm changes significantly, a swimmer may be moving faster without necessarily practicing the same movement they will use on race day.
FINIS SlipFin Pro gives swimmers and coaches another option for bridging that gap.
A Fin That Feels Less Like Equipment
One of the first things swimmers often notice about FINIS SlipFin Pro is how little equipment they feel around the foot.
The soft material creates a seal around the front portion of the foot while leaving the heel and ankle open. Rather than surrounding the entire foot, the design allows the swimmer to maintain more freedom through the ankle while still receiving assistance from the blade.
It can also be a comfortable alternative for swimmers who dislike heel straps or experience rubbing and pressure around the back of the foot.
SlipFin Pro can be used across all four strokes, making it an option for freestyle, backstroke, butterfly, breaststroke and IM training.
Its lighter level of assistance can be particularly useful when the goal is rhythm, timing, body position or controlled speed rather than maximum overload.
Courtesy: FINIS
Dip. Slip. Squeeze.
The strapless design may look unfamiliar, but putting FINIS SlipFin Pro on is intentionally simple.
First, dip the swimmer’s feet and the fins in the water. Next, slip each fin over the front portion of the correct foot. Then squeeze the toe area to release excess water and air.
That final squeeze creates the gentle vacuum effect that helps keep the fin securely in place.
One detail can look unusual the first time someone wears SlipFin Pro: the toes are not supposed to reach the very end of the fin.
A small amount of space at the front is intentional. That space allows the swimmer to squeeze out the remaining air and water and create the proper seal.
FINIS summarizes the process simply:
Dip. Slip. Squeeze. Swim.
Once swimmers understand the sequence, it quickly becomes second nature.
Courtesy: FINIS
A New Tool, Not a Replacement for Every Fin
FINIS SlipFin Pro was never intended to replace every fin already sitting on the pool deck.
Longer or more powerful fins still have an important role when the goal is resistance, strength, overload or maximum propulsion.
SlipFin Pro fills a different role.
It is designed for training where swimmers want to experience additional speed while maintaining a quicker kick tempo, freer ankle movement and a movement pattern that stays closer to their natural stroke.
That opens up opportunities for race-pace work, stroke development, underwater training, body-position work and assisted-to-unassisted swimming.
Ultimately, the question is less “Which fin is better?” and more “What are you trying to train?”
Different fins create different stimuli. FINIS SlipFin Pro simply gives swimmers and coaches another option.
Sizing by the Foot, Not the Shoe
FINIS SlipFin Pro is currently available in Small, Medium and Large. FINIS is also developing an Extra Small size, expected to be available later this year for younger swimmers and athletes with smaller feet.
Unlike many swim fins, sizing is determined by instep circumference rather than shoe size.
To measure, wrap a soft measuring tape around the top of the foot just in front of the ankle. Keep the tape flat and snug and record the measurement in centimeters.
| Size | Instep circumference |
| Small | 21–24.5 cm |
| Medium | 23.5–27 cm |
| Large | 26–28+ cm |
There is intentional overlap between sizes. For swimmers whose measurement falls between two sizes, FINIS recommends sizing down for a snugger, more performance-oriented fit or sizing up for a slightly more relaxed fit.
The full FINIS SlipFin Pro sizing guide can be viewed here.
For Teams and Programs
For teams interested in adding FINIS SlipFin Pro to their training equipment, FINIS recommends starting with a small assortment across each available size.
Because SlipFin Pro is sized by instep circumference rather than traditional shoe size, having a few pairs of Small, Medium and Large on hand allows swimmers to try the fins, identify the fit that feels most secure, and determine the right size before placing a larger team order.
FINIS offers special team pricing for qualifying programs. Coaches and team representatives can request team pricing here.
A Different Way to Think About Fin Training
The most obvious thing about FINIS SlipFin Pro may be its strapless shape, but the bigger idea is the training experience it creates.
Fins do not all need to accomplish the same thing.
Sometimes the goal is to create more resistance or maximize propulsion. Other times, the goal is to add speed while keeping the swimmer’s kick tempo and stroke rhythm closer to what they use without fins.
That is where FINIS SlipFin Pro is designed to fit.
Courtesy: FINIS
