The real indicator here is the foil NEMA tag, which was discontinued by 2001. This is a 1993 to 2001 model because of the foil Electromark NEMA tag. Before ~1993, Cooper used better quality NEMA tags with no logo on them at all and no source name in the corner. I have two NOS Cooper OVXs with the foil NEMA tags. They're made in 1995 and are 400W HPS with huge dual tap 120/480V ballasts.