Mine's a triple, I call it the "Roughing It!" set. As described early in Roughing It! by Mark Twain, there are three passengers (including him) in the stagecoach to Virginia city who are armed. They have (and I now have):
1) A Thurber and Allen pepperbox. Mine operates. I'm yet to load and fire it, but it will revolve and pop caps on all 6 chambers.
2) A Smith and Wesson model 1. Again mine operates, but I have to figure out how to manufacture some .22 short BP rounds for it so am yet to fire it
3) A Colt 1849 Pocket. Mine is a Colt reproduction (3rd generation, so Italian manufacure). Again haven't fired it but no reason it wouldn't fire.