Is this a disc or drum proportioning valve?

[LavaSurfer]

I'm going through the brake lines on my 67 C10 and someone along the years has converted to disc in the front and it looks like they have used 73-87 spindles and converted the ball joint, etc int he process. The new brake lines were bent, kinked, and routed poorly to say the least so I'm redoing that. It looks like the correct master cylinder, I just want to make sure I also have the correct proportioning valve and I haven't had much luck figuring this out. Here is what I have.