The Invector, or "Standard Invector" system" was introduced in 1983. A few years later, the Invector-Plus chokes were introduced to fit the new back-bored shotgun barrels. These two choke systems will not interchange. If you have screw-in chokes in your shotgun barrel, the kind of system you have will be stamped on the barrel near the receiver. You must use the proper choke system for your shotgun.
I don't think there is an invector plus model. Invector Plus is the choke system Browning uses on newer shotguns.
Either Invector or Invector+ depending on how it left the factory.
Browning did not make an Invector model. That is the type choke system of the shotgun.
Browning's web site has the current information.
You will have to call Browning to find out.
What is the question?
10-20 usd
Go to Browning.com and type "Invector Choke" in the search function.
Made in 1996
To change the choke of the shot
Browning made choke tubes.
Invector is a brand not a choke. Invector is a brand not a choke.