Originally Posted by Losligato
We've been lugging around a whole lot of water here in Southeast Asia. The MSR Dromedary bags have been really quite good. They collapse down nearly flat when empty then expand when full. They can take boiling water and can freeze with no problem. They have a strap around the outside and are easily secured to the back rack.

+1 I have used these for many years. I also have a
Shower Kit for mine. A black MSR bag left in the sun will get you a nice warm rinse off shower. I have several different sizes and use the one that fits the need. Typically I use the 4l one the most. Nothing says you have to fill it all the way up
Aaron