The stainless hip flasks with the hinged caps are certainly convenient. I have two, a handsome one given to me years ago by my brother, and a more rebellious one that was a gift from another foxhunter.
The problem with the hip flasks is their small capacity. They only hold 6 ounces. There is another item popular in this territory where people are serious about hydration. I’m not sure Wadsworth would approve, but it seems to be acceptable at local hunts. It’s a generic 16-ounce plastic flask in a leather case that clips to the D-rings. Unfortunately, mine suffered a minor injury last time I hunted, so that flask, filled with the locally popular rocknrye, will probably ride in my coat pocket the rest of the season, along with the hip flask of Bourbon that is a permanent pocket passenger. It’s important to be able to cater to a range of tastes.
One problem with the plastic flasks is that the cap is not tethered. This does require some additional dexterity. And occasionally there is a problem. Fortunately, I found a company that sells the caps in bulk quantities. So if a cap is lost, we just have to immediately consume any remaining contents, and then I dig into my cap stash at home for a replacement. I considered carrying a few spare caps in my pocket for emergencies, but fortunately lost caps are rare enough that it doesn’t seem necessary.
