evo.com | Hydro Flask Water Bottles > Oh no, lost the lid for your favorite Hydro Flask bottle? Don't despair, the Hydro Flask Standard Mouth Flex Cap is here to keep that baby going strong. Fits all Hydro Flask standard mouth bottles. Honeycomb Insulation(TM) Helps keep cold drinks cold and hot drinks hot. BPA-Free and Phthalate-Free Compatible with All Standard Mouth Bottles Durable, Stainless Steel Pivots | Hydro Flask Standard Mouth Flex Cap 2021 in Blue