I just got two of those used off of Craigslist... They have one long cross-piece at the bottom, going across the back, and two short ones on the sides to stabilize the legs. They didn't come with a bottom shelf, or the pegboard back. They did come with the top shelf and full-width drawer with roller bearing drawer slides. Without the bottom shelf, I think they were meant to be used as a tall shop desk-type bench.
Keeping one--it's the perfect height for making it a game-cleaning station down in the basement. I'm going to replace the top with a piece of white cutting board plastic from McMaster-Carr.
The other one is for sale. Anyone in the Atlanta area need one? $50.
-Brad