I just purchased an original repop antenna from the Truckshop and the rubber washer that goes between the mast base and the cab has a raised rib around the outside, like almost all washers I have seen for this type of application. Except here, it only goes around maybe 3/4's of the way around and is just flat at the remaining 1/4. Is this just a defect, or is this designed to either, fit against the cab beltline, or orient downward as a kinda of drain????
