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.
Either Invector or Invector+ depending on how it left the factory.
You will have to call Browning to find out.
Browning's web site has the current information.
What is the question?
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.
The 2 letters NX in the middle of your Browning Invector pump action shotgun indicates that it was made in the year 1993.
Look at the choke tubes.
Best bet is to have it examined by a good gunsmith.
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