Kiefer Training Swim Fins Foot pocket is soft, flexible, and comfortable enough to log countless hours in the pool, Kiefer Training Swim Fins are essential for swim workouts and swim training Easy on and off A short, curved, and firm blade fin improves kick efficiency and develops kick strength without overtraining muscles, allowing swimmers to focus on proper kick mechanics. Fins float to pool surface for easy collection Unisex fins designed to fit a range of approximately two shoe sizes; if you are between sizes please order up one size