Winchester Repeating Arms X Pump (SXP) - Manual (Page 11)

9
Faster pump-action. Inertia assists you as you pump the
forearm rearward to load for the next shot.
Most Super X Pump hunting models are fitted with the Invector-
Plus
™ interchangeable choke system. It allows you to change choke
constriction to the demands of the game being hunted or your shooting
situation. You can easily change the pattern size and density by simply
switching choke tubes. A variety of accessory choke tubes are available.