How can I identify the choke tubes that came with my Weatherby shotgun?

Choke tubes can be identified by the number and placement of small notches found on their muzzle ends. Be sure to clear and make safe any shotgun before looking at any installed chokes. Notches / Choke Constriction O / Extra Full I / Full II / Improved Modified III / Modified IIII / Improved Cylinder IIIII / Skeet IIIIII / Cylinder I-I / SC I II-II / SC II