Hydro Flask Wide Mouth BPA Free Travel Mug Hydro Flip Lid for Coffee (Not Leak Proof) The Wide Mouth Hydro Flip lid has a flip-top opening for easy access Fits the 12 oz, 16 oz, 18 oz, 32 oz, 40 oz and 64 oz Wide Mouth Hydro Flasks This lid is NOT leak-proof Convert your wide mouth bottle into the perfect thermos for coffee and hot beverages It never hurts to have extra lids!