Lightweight, round canteens are a vibe.  Not the sturdiest but you get points for style.  Comes with a sling strap (it sucks, too small, bad nylon) -- but it's serviceable and you can always loop another strap on through.  

High impact plastic body, lined with metal and faux wool,.  Would probably just throw this in the ruck up high and next to the body to carry water for when you get to camp.  Available in 4 Quart and .75 liter sizes.