Replacing battery tray. Coating? (Page 2/2) pmbrunelle JUN 18, 10:16 PM I don't know; my Fiero has been undergoing an overhaul for the last 2-1/2 years, with at least another 1/2 year before I'm "done". I'll know for sure when I drive the car. That said, the rivnuts look and feel quite beefy; I don't have doubts that they'll hold. How strong they are depends on the size and material as well; these are steel M6 rivnuts. If the rivnuts were a smaller size, or made of aluminium, I'm not sure they would be strong enough (doesn't mean they wouldn't hold though). I don't like aluminium rivnuts, because corrosion is accelerated when dissimilar metals touch each other (i.e. the aluminium rivnut touching the steel body). The downside of the steel rivnuts is that they're tougher to install; they may require a more expensive rivnut tool, with long handles, that can handle lots of force.