Finally we have the original plated vacuum fitting as the Tri-powers came with from the factory. This is an exact reproduction of the original.
This part is used to obtain vacuum advance ( usually for advance for distributor) off the rear of the center carb. Also is used when Brass T-fitting is used on center carb for vacuum advance on 1- side of t-fitting.
I do carry an after market brass vacuum fitting on the web site if you are looking for a less costly fitting.