If it is a stock gun it probably has a open cylinder unless someone has added a choke.
A shotgun barrel with a cylinder bore choke.
Cylinder bore- no choke at all.
Improved cylinder
Stevens 107b is a fixed cylinder bore. So in other words, no choke and not able to be choked.
They came in various barrel lengths and choke combinations. If it is not marked on the side of the barrel, you will have to pattern the shotgun to determine the choke
from smallest pattern to largest: full improved modified modified improved cylinder cylinder (no choke)
The Choke of a shotgun is the amount of barrel restriction at the muzzle end which affects the shot pattern. A full choke will keep the spray pattern of the pellets closer together farther out than if the barrel was not restricted at the muzzle. If there is no restriction at the muzzle, the choke is said to be cylinder choke or cylinder bore.
Invector is a brand not a choke. Invector is a brand not a choke.
Cylinder bore- which is no constriction at all.
4 notches = cylinder choke (open), and one notch = full choke (tight)
On a shotgun what choke will open up more improved cylinder or modified?
Approximate value on this shotgun is $130 - $200 depending on condition.