Denso Compressor Question

[Ezzz]

Hey guys, riding in my truck feels like so I'm trying to get the AC figured out. My 69 C10 has a 2006 4.8 from a silverado that came with the compressor. Initially it didn't wanna fit so I took a bolt off the back for a little extra room test fitting and misplaced it. Now everything fits, but I can't find any diagrams saying what the thing is called. Obviously it's a bolt, but it also looked like a breather. There was a tiny hole in the bottom where it goes in the compressor, and at the top it had two holes that looked like the let air out but not in? I've attached a pic, but if anyone knows what it's called, or better yet where I can find one I'd really appreciate it. Thanks

[First c10]

Ezzz, that little bolt as you say is a high pressure relief valve. Sorry I do not know the specifics for you. But someone will chime in here. Good luck. Oh and post a pick of your ride.....
Ok quick google search

Edit: Is this it? You can see the compressor model numbers this fits.

[Ezzz]

That's the one. Thanks a ton man, appreciate it.

[First c10]

no problem good luck!