The invector-plus tubes are longer choke taper inside and produces patterns with excellent uniform densities.It is set to industry constriction standards and have an excellent patterning.The choke tube is constructed of highly polished, 17-4 stainless steel for the ultimate in performance and durability.Approved: Lead OnlyType: FlushGauge: 12 GaugeConstriction Type: FullConfiguration: Invector PlusFinish: StainlessConstrictiondiameter: .035Chokes Included: 1Recommended For: 40+ ydsMaterial: 17-4 Stainless SteelPorted: No