Hard Knox was a Glam/Hair metal band that formed in tennesee in the mid 80's that released an EP, and then a full length album titled "Combat Alley". Hard Knox's lineup shifted throyghout their career, at one point they had Rick Ruhl on vocals, who would later go on to lead Every Mother's Nightmare. Hard Knox has issued a few albums, compiliations and re-issues over the years, all of which are very rare.