All common models have short barrels and originally fired the 5.75mm (.22 calibre) Velo-dog cartridge, although many produced after 1900 were chambered in .22 LR or .25 ACP rounds.
Alternative ammunition options existed such as cartridges loaded with cayenne pepper or dust,[4] or bullets made from wax, wood, or cork.
[5] Despite the low energy of the round, a suicide case was recorded where a woman shot herself twice in the temple with a .25 (6.35 mm) Velo-dog revolver before succumbing.
[6] Today, the Velo-Dog term is used for a broad assortment of Euro and American pocket revolvers in various calibers by diverse (and often anonymous) makers.
The most prolific production was from the turn of the 20th century to World War I, when a cottage industry sprung up and there was a proliferation of Velo-Dogs of various standards.