Small hammer for knocking parts off the build plate. There's a .15mm gap between the handle and the head, you may need to rescale, sand, or glue to get it to fit depending on your printer/settings. There are two sizes of hammer, the handle for the small and large hammers are almost identical and probably interchangeable.

I'd recommend printing the head at 100% infill to make it heavy enough to be useful (or you can try a denser filament).