Strong Yet Flexible, The Standard Mouth Flex Cap Is The Perfect Companion For Spontaneous Campouts, Epic Road Trips, And Everything In Between. Made With Stainless Steel Pivots And An Easy-to-carry Strap, This Cap Has Honeycomb Insulation To Help Keep Your Drinks Cold For Up To 24 Hours Or Hot Up To 12. Pair It With Any Of Our Standard Mouth Bottles.