Carlsons long beard turkey choke tube has been designed to produce the best patterns when shooting winchesters new long beard turkey loads.This new ammunition features shot-lok technology that allows for the tightest patterns and longer downrange reach.*no steel shot larger than #4 may be used in our turkey choke tubesGauge: 12 GaugeConstriction Type: TurkeyConfiguration: RetayConstrictiondiameter: .665Material: 17-4 Stainless Steel