I'm very pleased with my Sony MDR-7506 headphones. Once upon a time I bought cheaper headphones and later I regretted my purchase and ended up getting the 7506. Headphones are a very personal thing like speakers, you should listen and try them out, I am not saying these are "the best" or "the right" ones, just the ones I own and really like because they are flat, accurate monitoring headphones with pretty good isolation from outside noise. Many rental houses have these in their inventory, as they are considered "standard issue" by many sound professionals, so they are easy to get ahold of and try.

Stu,
You are more than likely correct, for those numbers and letters were the only ones on the mike and the box had NO information other than the name.
tom