It is the extra bottle with top for the gun.
I found that the easiest way to fill the bottles is to warm the wax/film to 110F. I used a thermometer, pot with a lip and a hot plate. It will then flow like a liquid and you can than fill the bottles up. When it cools off, back to it's original form it will go. If you don't warm it up first, you will find filling the bottles is a mess. You don't want that.
Reviewed by: Adam Flax from Newton, MA.