The SwimFin shark fin is made for swimming. Worn on the back, it gives the arms and body complete freedom of movement.
Note: SwimFin comes in one size only, but is adjustable to fit small children (about age 3) to adult.
Though the packaging states it is for younger kids, we've found that it's fun for people of all ages! It provides buoyancy and functions as a flotation device for kids just learning to swim, and it's loads of fun for older, stronger swimmers who just want to play shark in the pool.
The inventor of the SwimFin shark fin, Kevin Moseley, is 6' 3" tall, weighs over 200 lbs and the SwimFin will keep him afloat (he has personally tested this.) The buoyancy doesn't get in the way of a strong swimmer who just wants to play shark either.
The SwimFin must be used under constant, capable supervision.