In 1968, SEALs serving in South Vietnam reported to the Navy that they needed more firepower. Back in the United States, the service’s engineers rushed to help, crafting various weapons and accessories, including some particularly weird looking magazines.

Task & Purpose had the opportunity to take a closer look at these rare prototype “Mod 1” and “Mod 2” magazines behind the scenes at the Naval Heritage and History Command in Washington, D.C.