T
The Old Guy I use CNOC bags for my hydration needs but have Smart Water bottles in holsters on my pack shoulder harness's to hold two liter smart water bottles.
I realize I am different than a lot of folks but I do not like the sports bottle caps (the part that you have to pull up to gain access to the water), I like to take a full "gulp" of water without having to work for it. I have a tendency to drop the caps on the smart water bottles.
So, purchased these and replaced those caps. Now I can gulp away and not loose the cap!