Went to an auction, today and bought a fender (only 1) for a box trailer, that had lost part of the original, due to an axle failure. I didn't take any measurements, and the fender was aluminum, not FG, like the original, but I only paid $25 for it. Didn't have any measurements of the original, with me, so I just eyeballed it... got home, and it fit perfect! So it's aluminum, you can't see both sides of a box trailer, at the same time. I was quoted $150 for a pair, 2 years ago, so I guess I scored pretty big...