I have them on my class C. A quick look on Amazon shows them available at 85psi and 95psi. If you can't find 90psi, go with the 85psi - it will give you an earlier warning.
I like them so much, I put them on my FoldnRoll also. Nice to be able to just take a quick look and know the pressure is good.
1975 American Clipper RV with Dodge 360 (photo in profile)
1998 American Clipper Fold n Roll Folding Trailer
Both born in Morgan Hill, CA to Irv Perch (Daddy of the Aristocrat trailers)