Essentials are things that are very difficult to make or obtain in the wilderniss. You need a container for water as it is the most essential commodity for a human.
You can survive 3 minutes without air, 3 days without water & 3 weeks without food.
The most used container is the Nalgene bottle as it is unbreakable, BPA free and a lot of aftermarket products (like waterfilters, insulation, bags…) are designed to be compatible.
However you can’t use it to cook water, the most basic and effective method to produce drinking water. That’s why I use a stainless steel version of the Nalgene bottle. I attached a bail to it so can be suspended over a fire (coffee or tea anyone?) and has a little pink splash guard on it, fancy. This is very handy when you try to drink while you’re in a bumping 4×4 …
The stainless steel version is made by Guyot Designs, every production run sells out quickly so get one as soon as you can.
Also it can be used as a hammer…