Do your boys a favor and don't buy a dollar more than these. I highly recommend airing them out and watching a YouTube video on how to set them up to stop at your desired psi. I blow my 285/75/17.33" from 33psi to 12psi in about 10 minutes. Make sure you open them up and lube the o-rings and everything with some wd-40 and they work a lot better .