The Kaw Valley Precision Browning® Invector Extended Choke Tube features Swiss lathe-machined 17-4 stainless steel construction with a black nitride finish for unparalleled strength and durability. The extended forcing cone ensures a more consistent pattern down range, while the choke restriction is laser engraved on the end for easy reference. Compatible with lead, nickel, tungsten, copper-plated, and heavy shot. Works with traditional choke tube wrenches. Fits Winchester 1200, 1300, 1400, 1500, Ranger; and Mossberg 500, 535, 930, Maverick 88. No steel shot larger than #BB should be used in choke tubes tighter than full constriction.