If you remove the tool tray beside the battery box, you might get a small one in there. One of the older members on here removed everything around the battery, made a box that fit in there, switched to a lithium battery, and had a good bit of storage space. Might be room for a 1 or 2 pound bottle. You can get NO2 bottles as small as 3.5 ounces, but the shot doesn't last long.