https://www.offgridweb.com/gear/unconventional-weapon-the-oss-stinger-pen-gun/
Unconventional Weapon: The OSS Stinger Pen Gun | RECOIL OFFGRID
Jul 26, 2018 - During WWII, the Office of Strategic Services (OSS) developed the Stinger. This single-use covert gun resembles a pen and fires a .22 Short cartridge.
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