Oh man I didn't know that came in pen form. I came here to recommend Birchwood Casey's aluminum black restorer but the pen version looks super convenient.
give it a rattle can spraypaint camo job or if #blackriflesmatter just hit it with an aluminium black pen to get rid of the shine and call it good.
I bought this one, but haven't used it yet.
You put the tool in the press and lower it to the jig. The cone does centers. The cylinder finds edges. Move the jig around (or work your xy to get it centered if you have one) until the center is concentric with the tool shaft. Then lock the part down. Then raise the press and switch to your cutting tool.
While you're at it, hit up Maryland. We have a VERY similar bill working it's way through our general assembly:
This … is … amazing. Did you buy from Amazon? https://www.amazon.com/Engraver-Machine-Marking-Engraving-175×175mm/dp/B083XKPLVP/ref=gp_aw_ybh_a_1?_encoding=UTF8&psc=1&refRID=J3X1W72NBMEMSWRTMMZ2