Bursch Muffler (Question)

[jksinuc]

I just purchased a two inlet Bursch muffler. I have a 1976 911S with the older 1974 style exhaust setup.

The muffler showed up with a small 1/2" tube that runs from the pipes at the inlet of the side of the mufller to a threaded fitting. I am not sure what this connection is for.

I am assuming that this tube is for a car equipped with an exhaust gas recirulation valve, but when I look at the factory manuals I cannot find it.

I am thinking about caping the fitting as I have nothing to connect it to. Does anyone know what this connection is?