I cannot figure out for the life of me what the thing is called, but I'm switching from the standard greddy drain to a SS line and need to cap off the old return. Anyone know where I can get one or what the hell it's actually called?

 

See here > https://www.miataturbo.net/forum/t31252/

Vash-

 

Damn, I was searching forever trying to find a post like that. Thanks!