This is what I'm working on today. This is under my kitchen sink, and it is leaking just enough to bug me.
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So this is taken from laying on my back under the sink looking up. The round thing on the left is actually on the cold side.
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And here's a close up of the thing that is actually leaking. It does not seem to be connected to anything, and I tried to turn the wingnuts by hand (righty-tighty) and it's pretty tight.
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So now what?