https://www.printables.com/model/465940-voron-stealthburner-cheap-nozzle-camera-endoscope-
Been running for months now in a heated chamber! These cameras should be easy to adapt to most printers. It was only supposed to be a temporary addition to fit for troubleshooting, but it’s holding up to almost constant use really well!
There’s a really nice nozzle cam available for Voron now. You have to print the front cover part again, but it has a housing for a 4K nozzle cam. Much more pricy, but incredible quality, invisible and a bit easier to connect.