British Military RAF Zarges Style Aluminium Transport Flight Storage Case Box. A Large military drop box all latches work the paint is peeling in places the inside still has its foam protection on from its original use in the military. I don't know if it's a zarges box but looks very similar. The box could be stripped back to reveal the aluminium behind.
A do have another one of these they do look good in pairs. Please study the photos for the best description.