Winchester Signature choke tubes are unsurpassed in the shotgun industry. In collaboration with Briley®, one of the most renowned makers of choke tubes in the world, the Invector-Plus™ and Standard Invector™ tubes are carefully machined from the best materials and calibrated to the strictest tolerances to deliver shot patterns exceeding your highest expectations. Installing these tubes in your barrel insures that you are getting optimum patterning for the most challenging of wild game and the most difficult presentations in clay target shooting.