Bandpass Question.

OK I'm looking at this sub and it gives the bandpass numbers. It claims that the aitspace required is 1.6 cubuc feet of airspace. But which chamber is this number for? Is this for the front or rear chamber in a bandpass box? I say it is for the rear chamber but I just want to make sure.

Maybe its the overall airspace like .9 on the ported side and .7 on the sealed side?? What sub is it, a vega?

MTX Thunder 8000 Series.