This is a fantastic pair of Oceanic Vortex V-8 split fins These Oceanic Fins feature: Patented Nature's Wing propeller fin technology Advanced composite materials for ideal flex and memory Rigid side rails for increased lift and efficiency Ergonomically designed foot pocket accommodates virtually all foot sizes and boot styles State-of-the-art materials Angled blade for preferred angle of attack Easy on/off fin strap with thumb loop Easy adjust quick-release buckles Excellent effort/thrust ratio Provides greater thrust while reducing muscle fatigue Less effort and drag per kick Like a pair of underwater wings Unrivaled freedom of movement uderwater These super Vortex V-8 Split fins are Quality at an amazing price!!!