Good imperial bolts.

Does the US make the machines that make the bolts any more?

And what if you needed metric bolts?

"I Tried To Make Something In America (The Smarter Scrubber Experiment)" https://youtu.be/3ZTGwcHQfLY talks about the trouble he had finding US made bolts and I seem to remember he found out he'd been scammed and was sold Chinese bolts anyway? (Edit: Skip to around 17m35s)