Do you live in a RV?

It's too blurry to be sure, but that looks like a threaded fitting at the wall. If that's the case, shut off the water and spin that contraption of a valve off and replace it with a valve with a normal thread fitting on the hose side. Attach the hose, secure both sides, and turn the water and then valve on.

You and your assumed female companion should both start dating men.

I screwed up one of those recently. Shut off valve broke, tried removing it, and ended up kinking the copper line under the house. None of my friends and I could fit around the duct under the house to fix it. Called a plumber, told him to bring a tiny guy, and he did. Two hours and $280 later, the copper line was replaced.

LMAO

No, I live in a two-story house. This is the upstairs bathroom.

Yeah, I think I get it now. Unlike the kitchen faucet where I was able to easily re-attach the new supply line to the existing stop-valve, I'm going to have to replace the stop valve at the wall.

I'm told a lot of 80's porn begins this way. Let me guess, you have a moving truck and need to run to Lowes in the next town over....and by Lowes, I mean the closet to work the camera....

Might as well fix this up while we're there.

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:clap:

It's all but leaking at the wall connection anyways. Just don't **** up that wall fitting or the odds of the plumber plumbing your, still assumed female, significant other increases drastically when you're forced to have him come clean up your mess.

I've never seen a shutoff valve with flex permanently attached to it, wtf kind of shit is that?

Ha, pretty much word for word what I was about to respond with.

Thats what I think. The calcification is due most likely to 2 different types metals. Behind the wall is most likely copper and that appears to be an Galvanized iron fitting through the wall to a copper and chrome valve. Very likely leaking at valve and copper pipe behind wall where iron pipe threads in. You need to open that wall up to see whats behind and what kind of water damage if any. Get 2 pipe wrenches one to keep minimal movement the copper line the other for steady counter clockwise pressure on the iron nipple. It will break loose. Sometimes the nipple breaks off if its really old and rusted then its a bitch. Steady pressure and even. Take old nipple to hardware store get new maybe a bit longer and new shut off valve, pipe thread tape or putty replace get new flexable service line and your gold.

You can't unscrew the valve and then pull the nut off?

??

The nut that's there is probably held on by a compression ring


That whole valve body should unscrew out of that nut.

Then you can try to screw in a new style valve body with a 3/8 compression outlet

Or

If it leaks , pull the nut off with a compression nut puller

I bet its the hot water side isn't it? Its always the one to FU first if it is corroded bad do the other side regardless if its having problems now or not. It will be soon to follow. You dont want that bursting because it always happens when your out town. Next thing you know you have a water remediation crew there for the next week or two. You think a plumber will rape ya think again.

Maybe but I would want to know whats going on with that nipple on other side the wall. Just the way my Dad taught me you fix the bigger problem instead of put a band aid on it. An ounce of prevention is worth a pound of cure. Can hear him saying it now.

If the drywall is not soft why would there be a problem behind t he wall?

Take some Clorox and see if it's just a surface stain.

I've seen much worse...it doesn't look like a leak imo