Solid, proven product. Have more faith in these things than in the roof ducts commonly offered for recreational vehicles. Doesn't build that high, is aerodynamic and you can still get at it afterwards without damaging sealing or adhesive surfaces again. Serves as cable entry for roof PV on Sprinter
The product is fine, however 1'' plugs only fit through the base and not through the cable entry. If you do not want to cut off the plug because it is welded to the cable so that it is watertight, you must choose DS30-P, for example. I am now using the Scanstrut DS30-P for the breakthrough above the waterline to be able to connect a Simrad Totalscan. You don't really want to cut through the expensive Simrad cable.