Eco-friendly fabric made from 100% recycled plastic bottles, whose 4-way stretch air mesh offer exceptional breathability even when your feet get hot and sweaty. Patented F.A.S.T. technology makes the shoes easy to slip on hands-free, without need to bend over, wiggle your feet, or crush the heel. Shoe is marked as a sample with no size. I wear a size 9.5/10 and they fit me perfectly. S4-387