I have several different boxes from this company. Unfortunately, I cannot describe the cartridges as I have none of them. They are totally illegal in my state. For what would appear to have been loaded ammunition from the label, I have a yellow box, probably like the one you describe, end-labeled simply “9mm Luger Cal.” on three lines, printed on a white stock on label. The black box, with gold print, has a small label that says merely “9MM LUGER” on one line. I also have a green box that seems to have been for projectiles only, labeled similarly to the others as “EXPLODER BULLETS .355 115 Grain FOR RELOADERS.”
According to all the box labels, the company is Bingham Ltd., P. O. Box 47026, Atlanta, Georgia 30362. None of the boxes show the company name as “Squires Bingham,” a name I believe is owned by a Philippine ammunition maker. The book "Handbuch der Pistolen- und Revolver- Patronen (Manual of Pistola nd Revolver Cartridges,), newest combined Volumes I,II,III edition, on page 642, indicates the founder of the Bingham Ltd., 1775-C Wilwat Narcross, Georgia (probably the factory address rather than the P.O. Box as previously given) was Sidney Brigadier, “… who occupied himself with the production of this kind of ammunition; he manufactured it above all by modifying already fabricated rounds. He employed for this purposed to a large extent the “Super Vel” ammunition.”
I have another box that was for similar ammunition, I believe, from the comany of "EXAMMO, Division of Precision Products of Washington, Inc., Spokane, Washington. I believe it is older than the Bingham production. It is also for 9mm Luger ammunition (10 cartridges). I doubt the two firms are related.
One thing I do know about the cartridges. They were made in various calibers, as I know I have boxes from “Exploder” brand in calibers other than 9mm Para. Also, they never had their own headstamp, or at least I am not aware of one. They were loaded in available commercial brass, so headstamps could vary from box to box and caliber to caliber.
Most of these types of loads are based on jacketed, hollow-point bullets, with the hollow cavities filled in with expolosive, impact detonated material. They are often sealed in red lacquer, especially if other types (Incendiary, etc) are made, but I suppose not always. I have seen them in collections with yellow tips at least - I mean these types - I do not know if they were Exploder brand and they may not have been exploder cartridges, but rather some other pyrotechical loading.
Sorry I could not help more - a big disadvantage in helping collectors and LE identify this stuff when you can’t have the cartridges.