EVA CONSTRUCTION Stress-crack and UV resistant Ethylene-vinyl Acetate (EVA) construction makes the Tilos Starburst Fin virtually indestructible. The "rubber-like" EVA is an elastomeric polymer that is sturdy, yet flexible and lightweight, allowing for a smooth and buttery feel with less water resistance. Weighing in at only 1.5lbs per fin. Anti-slip fin soles prevents you from sliding around on slippery surfaces. Optimized water flow trench and drain holes. The soft and comfortable foot pocket is designed to be wide enough to securely fit any type of dive boot. Adjustable fin strap allows the fin to fit a wide variety of sizes. From USA size 4 to 15.