Browning Invector Plus 12 Gauge Rooster XR Choke TubesFeatures Carlson's Exclusive TST (Triple Shot Technology) which results in reduced pellet deformation, shortened shot strings and less flyers. Our Rooster XR choke tube is manufactured from 17-4 stainless steel and has been specifically designed to produce the best patterns when shooting Winchester’s New Rooster XR ammunition. Featuring the new Shot-Lok Technology that produces the tightest patterns and highest down range energy when compared to other game loads on the market. These chokes come in either Early Season (LM) or Late Season (IM) constrictions to accommodate nearly all hunting situations. We have designed these chokes to handle lead, steel, or Hevi-Shot so they can be used for either upland game or waterfowl hunting with great results.