Lightweight, high performance dual-composite fin blade for ultimate comfort, efficiency and performance. 
Features:
Composite Material: Blend of Thermal Plastic Rubber (TPR) and Polypropylene
Flexible Power Thrust Channels & Side Rails
Blade Design Provides Uncompromising Power and Efficiency
Blade Power Vents Reduce Stress while Accelerating Water Over the Blade
Over-sized Blade Design for Increased Thrust and Propulsion
Foot Pocket Design Significantly Reduce Drag
Easy On and Off
Bungee style with Squeeze Style" Quick-Release Buckles
Large Pull-Tab Holes in Straps for Grip
Sizing: 
X-Small: 5-6
Small: 7-8
Medium: 8-10
Large: 11-12
X-Large: 13-14