This slip-on shoe uses advanced construction techniques, including being more durable. Featuring a contoured arch support and articulated heel strap. Spend your days in and out of the water with a pair of Hydro Slides! SIZING: The Hydro Slide is designed to be an easy on / easy off shoe, so sizing is generous. If you normally wear a half size in Merrell footwear, we suggest you size down in this product, rather than ordering the ½ size larger.