This little canteen is great for any day hike. It can easily fit in large parka pockets or stow quickly in your bag. Some of the canteens come with a clasp so you can easily hook it to a belt loop or your pack. These will come in various colors but will all be close to an olive green color. 

They carry around 0.75 liters or about 25oz. 
 
If you do decide to drink from this, I suggest cleaning the inside well. These have been in storage for a long time. After a good clean, you should be good to go.