Browning ckoke tube marking are
Full=1 notch
Improved Mod=2 Notches
Modified=3
Improved Cyl-4
Skeet =5
and cylinder choke I think has no notches but have not seen one for a while so do not quote me on that one. You Can not confuse the two as Invecter chokes are around one inch in length while the Invecter plus measure 2.4 inches in length. This is for standard Browning chokes that are fully enclosed by the barrells, other after market chokes that extend from the barrells are a different matter.
