Sheet metal with some good welding and finish work. I wondered for a bit if they were stainless. Nicely done any way. All the screw holes are marked on the bumpers but I didn't bother taking any more detailed pictures. Mark at Eurotech thought they were better than most of the stuff he has seen. We made a comparison of a set of C2 bumpers that just came in from Better Bodies and the Shaw pieces were more substantial. Gotta say though neither pair is much more than a bit of thin fiber glass. (we are going to be dropping some serious weight here boys
The Shaw pieces seemed more substantial and were more rigid. But the Better Bodies parts are a different type of glass and are more flexable intentionally.
If it isn't raining tomorrow I can get some more detailed pictures, just tell me what you want to see. I have a Ruf lip that is going on from Pie and it looks like that won't be a problem from Mark's comments. The light buckets need the newer and slightly larger fog lights than my '79. The '84 on should work fine. Haven't decided to use them as a driving light, keep the fogs or make them air ducts for my 930 brakes.