Are the rivnuts in the roof (for the roof rails) waterproof on the outside?

It looks to me like they are zinc coated, and it seems like they do have some sort of sealing on the interface at the roof. And they are closed at the end so no concern about water getting in. They also used the six-sided kind of rivnut which are very strong. Consider me impressed:

sqenixs said:

It looks to me like they are zinc coated, and it seems like they do have some sort of sealing on the interface at the roof. And they are closed at the end so no concern about water getting in. They also used the six-sided kind of rivnut which are very strong. Consider me impressed:

Click to expand...

The HF ham radio antenna clamped to the the right rail of my Latitude requires a low impedance connection from the cable shield to the roof sheet metal, which serves as a ground plane. I ran a brass strip from the base mount back to one of the rail fasteners, but noticed some corrosion the following year, so I'd say they're nothing special. As shown in this photo, I replaced both original M6 screws with stainless, coated the threads with silicone dielectric grease, and haven't had much trouble since. Twice a year, I disconnect the cable from the transceiver and measure series resistance through the outer conductor back to the chassis. If it exceeds a quarter ohm, this would indicate a problem, but so far the rivnuts have maintained a solid connection to the roof frame.