FINIS Positive Drive Fins - High-Quality Swim Fins for Men and Women - Swim Flippers to Use with All Four Swim Strokes - Swimming Fins for Swimming and Pool Accessories - X-Large, Yellow

The Positive Drive Fins (PDF's) from FINIS use a unique ellipsoidal blade to generate correct propulsion in all four swim strokes. The unique asymmetrical blade design allows the swimmer to build power while promoting a natural inward supination kick style for butterfly, backstroke, and freestyle swimming strokes. The PDF's use an ergonomic foot pocket to comfortably place feet in an ideal swimming position. The heel strap secures the fin in place while you swim, allowing feet to flex more naturally. A closed-toe design provides superior energy transfer from leg to foot. The PDF's will increase leg strength, foot speed, and ankle flexibility for all four swim strokes, making the fins great for individual medley training.