The NEOSLING was designed to hold all popular stainless steel bottles, as well as sports drinks or other popular beverages. With a wide, soft and stretchy Neoprene Adjustable Strap, the NEOSLING fits all body types comfortably over the shoulder or around the waist without digging in or chafing. The neoprene (think "wet suit") material in the NEOSLING insulates bottles in all seasons from heat or cold, keeping your water or beverage at the temperature you expect it to be for up to four hours.