In past centuries, gentlemen carried flintlock solitary-shot pocket pistols, sometimes even with somewhat folding bayonet on them, within their tailcoat pockets. That gave technique to the percussion solitary-shot that even these days nonetheless bears a version of Henry Deringer of Philadelphia’s identify. William Elliott’s Double Derringer, as created by Remington, https://lifecardofficial.com/product/switch-gun-22-lr/