The leash is great for riders to keep hold of their sled as they climb the hills. * The Zipfy leash also acts as a safety cord to avoid runaway sleds. * In instances where a ski resort allows Zipfy on the slopes (typically in a designated area or for a special competitive event) the resort operator will require Zipfy riders to have a leash to allow them to go on chair lifts. * Designed for Zipfy Classic, but also works with Zipfy Junior.