it is a canteen (mounted to the frame). I can use it for anything to drink, I use it for iced Redbull, But you can use it as an extra gas can on the road for long hauls. It was my choice to use it for a drink canteen, cause if I used it for extra gas, that would be the only thing you can hold in it after that. Unless I take up drinking gas. I drink an occassional Martini, does that count??!! LOL Sean at www.StarParts.org I can make ya one if you like?