This is the 'Outside' of the patch panel. I used the typical 4" Dryer Duct with a twist. This is New England after all, and weather can get chilly out. First I took 11 pieces of 3/4" PVC conduit and rolled newspaper into a tube and inserted it into the PVC Conduit. I then filled these with Polyurethane foam. I then placed all these conduits inside the dryer vent along with a 1 1/2" copper strap for the station ground (I insulated the strap from the aluminum dryer vent). I filled all the voids with the same foam. The newspaper in the conduit created a sleeve for the foam making it easy to slide out when it was time to put in a cable. Now I have an expandable, insulated and sealed pass through. Once a cable goes through, I used Duct Seal (Monkey - Uhm - Stuff) to keep everything cold tight. I also used a Stainless Steel box I acquired over the years to make the whole thing weather tight. After drilling a few holes in the sides, I used more TransiTraps to provide non-tower mounted connections.