Blu Wave's 10' coil SUP ankle leash is ideally suited for flat water paddling or use in small to medium sized surf. We recommend use of a leash in most situations when using our SUPs as a safety precaution along with a personal floatation device. Do not use an ankle leash when paddling fast moving water (eg. river whitewater). For surfing select "Straight Leash (surf)" - available in Blu only.