These CNC'd strips are profiled for a perfect fit the along the sides of the vent when it is positioned in the bay where the OEM roof beams are 14" apart. This is a very common location for RV vents on the 148 and 130 wheelbase Transit regular length high and mid roof vans. Fits Medium/High Roof Vans.
Please note that the 130WB does not use what we call "Rear Bay" strips. It will be either Mid Bay or Front Bay.
The support strips are expanded PVC and bonded to the roof with a thick (1/2 inch) bead of 3M Windoweld or equivalent adhesive. They are more flexible than wood and plenty strong to support the vent and keep it from jiggling.They also provide a backing for the screws that hold up the vent interior bezel. They should be placed 1/4" away from the edge of the hole so the screws for the vent go into the strips.
If you have questions about this product you can call Hein at 541-49O-5O98