This is a matchlock pistol made by an opportunistic gunsmith. He managed to buy up a bunch of old handgonnes at bargain basement price thanks to being friends with an arms merchant who dealt in used weaponry. Handgonnes being superseded by the newer matchlocks and as such many of them were being recycled. This gunsmith also recycled them, but he did not melt them down first. He took the barrels off of them, added a pan to their sides and fixed them into new frames with a pistol mechanism to avoid having to forge barrels from scratch. No two of them are exactly alike. The resulting pistols were heavy and somewhat unsafe, but they were dirt cheap and so found their place on the market. In particular they found use by sailors, pirates, knights with an abundance of sons that they have to outfit for war and junior members of cavalry mercenary companies. People which have use for said weapons, but are on a shoestring budget.