Factory Browning Invector Plus 20 Gauge Cylinder Choke Tube. Longer choke taper inside Invector-Plus choke tubes for use with back-bored barrels. Produces excellent patterns with excellent uniform densities. All Browning tubes are set to industry constriction standards. Flush fit does not extend beyond end of barrel. Constructed of highly polished, 17-4 stainless steel for the ultimate in performance and durability. Made in the USA. Specs: - Material: 17-4 Stainless Steel - Color: Stainless Steel - Pockets: Stainless - Choke Gauge: 20 - Choke Pattern Percentage: 15% - 45% - Choke Notches: No Notches - Weight: 4.8 Ounces