Thanks. I hope it works out!

You seem like you know what you’re doing, but since you mentioned it:

If you’re worried about leaks, you can use Nylog White on the threads. It’s food rated and works for your liquid and co2 gas connections. In theory, it’s also not supposed to harden and make your fittings impossible to unscrew.

Looks like 3/8" NPT Schrader valve connection to me, but I’m not an expert on the matter.

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You don’t need an online community to freecycle! Friends and coworkers often have old laptops and monitors lying around and some are also in need of laptops and monitors. I clean them up, do a proper drive wipe, install the OS of choice for that person, and pass them on to their next owner. Anything to prevent working hardware from going to an e-waste bin.