When you’re using a shotgun, it comes in handy to have a lot of extra shells available to use whenever you need them. Most shotgun owners will add a carrier attachment to the side of their shotgun so they can hold more shells right on their weapon. While this might be good for immediately pulling an extra shell out and loading it into the chamber quickly, carriers are limited in the number of shells they can hold. That is why you should have a special ammo pouch that can hold dozens of shells. This would be a pouch that you carry on your belt so the ammo inside of it is readily available at any time you need it.
I know that a lot of readers of Rem870.com blog like tactical stuff. Here is review of the 5.11 Tactical PUSH Pack which I used during 2-week vacation.