CLEVER IDEA THAT WORKS
This mug is well made from firm but quite flexible materials. The twist lock feature securely prevents any leaks. Mostly I carry it in my car for when my pooch needs a quick drink - and he approves of it. As the bottle nears 'empty', in order to get the 'last drop', it will be necessary to twist the lock closed, remove the entire lid and pour the remaining water into the cup. Works for me.