The back bathroom sink faucet is dripping. This has fallen on me to fix in the upcoming days.
What kind of fitting am I looking at on the copper pipe end of the shut off valve?

I put this in many moons ago and can't remember now.
The faucet doesn't have any means of removing just the handle to replace a cartridge. I was thrifty back then.
The shut off valve is stuck open as well. I'm waiting for a time when we can go without water if needed for a time before tackling getting them working. With the heat we're having today I don't want to shut down the water system while I futz with this job.
Did I tell you I hate plumbing jobs?
I don't bend that way any more but don't have a real choice this time.