I'm guessing from the price you got it from
Rockin' Tool Boxes. I bought one as well, mine is a prototype 56" EX5622 i think. Different layout than the ones now, taller with a bigger top hatch. I paid $900 for what new would have been $1999. Mine has the "grip latches" like the Masterforce boxes they sell at Menards. I suspect the same company builds these as well as the Tool Vault stuff. Very nice for the money.