GSI Bottle Cup 24 oz 

This is the larger size bottle cup from GSI. Perfect to nest in your Nalgene or other standard 1 liter bottle to keep in your bag. It’s rugged, lightweight, compact, and multi-tasking – making it perfect for your Hiking or Go Bag. Handles fold around the bottle.

24-fluid-ounce capacity; measures 4.1 x 4.1 x 4.4 inches, weighs 8 ounces

Nalgene is purchased separately here.

From GSI: 

Is it a cup? Is it a pot? Either way you use it, this rugged little cup is perfectly sized for solo camping and backpacking.

Cook ramen and eat from the pot, then make cocoa afterwards it’s the one vessel you’ll need for any ultra-lightweight adventure. The shape is designed to fit around a standard 1-liter water bottle (or store a small fuel canister for your stove), so it won’t take up too much room in your pack.

Solid Glacier stainless steel construction will hold up to years of use. Wire handles fold flat to save space, then extend for cooking or a little bit of extra reach so you don’t end up in the creek.