Leading brands like Life Factory or Hydro Flask sell their bottles with two caps: One being leak-proof, the other one easy to drink from - but not leak-proof any more. The new - and intern. pat. appl. filed - JuNiki's comes with a double necked cap, leak-proof, one smaller opening to drink, one bigger for easy refilling. Perfect new world. Buy one
JuNiki's: The World's Most Convenient & Hygienic Flask 2.0Easiest Filling, Drinking (without Spilling) & CleaningJul 2018