Sorry, on my other answer I said the other .45LC shotshells are #12, they're actually #9. Still, these #4's are have a further effective range than the #9's.
Hi! No problem, these pest control shotshells can be a bit confusing. The #12 is a very small pellet, and has been used for a long time to control pests no bigger than a rat (usually in/around barns, etc.) at very close ranges. The #4 is a newer upgrade, the pellets are quite a bit larger so they travel a little further & retain a little more power when they hit the target. Neither would be suitable as a self-defense or hunting round at all, they just don't have enough power. But for mice, rats, and snakes at close range they get the job done. Hope that helps!