Since the original post was before I discovered this wonderful site, I couldn't put my two cents worth in. What is needed to know about it? The box was a specially designed carrier for what was considered the essential tools and materials for an engineer squad to operate, whether in combat or not. It housed compartments made to hold all of the tools in a uniform way which, when opened, one familiar with the layout, could spot a missing item instantly. There was usually a diagram of the box on the inside of the lid in which was shown the compartments and, as Dr. Matts photos show, a list of the tools and materials and the quantities that were supposed to be present in each, i.e., an inventory. We used these in the USMC EOD and most of the tools were still around when I retired in 2000. Slight updates, such as more efficient blasting machines and blasters circuit testers, were added, but on the whole things like firing wire and cap crimpers don't change much. I don't know if I have the engineer pub in my set, but I think FM 5-25 (?) Demolition Materials should have a description of the set in it. Cheers, Bruce.