Besides the Breech Plug Wrench and the capper/de-capper, there are 2 allen wrenches in the kit. One for the stock and one for the sight adjustments. If yours is scoped, its no big deal. If you're using the open sights, you'll need the other allen wrench. It is very small. My basic allen wrench set in my tool box did not have one that small but I'm sure a hardware store would have it. You're looking at something less than 1mm. I don't know the exact size so you'll need to experiment somehow.