Janney started out as a wholesale hardware store in Minnesota. The "invincible" refers to a barrel upgrade that was an option in shotguns like this. I'm no expert, but a quick search of Janney double barrel shotguns reveals that even fancy ones go for little money ($100 for one with an inlaid silver hunting dog, for example). Likely, it was a gun you could purchase from the Janney hardware catalog. I've got a catalog-bought black-powder double-barrel shotgun, and it's worth maybe a hundred bucks. The "invincible" upgrade makes it a little more heavy duty -- mine is the el-cheapo stock catalog gun, one known for a barrel so cheaply made that it often exploded or twisted with regular use.