These exceptional tubes extend beyond the end of the barrel for easy removal and installation. They are tough with their stainless steel construction with black oxide finish and laser-etched gold accent band. If you are looking to upgrade from flush mount Invector-Plus tubes, this is an excellent tube to do it with. This choke tube has a Minimum gap geometry plus high-resolution RMS finish reduce plastic buildup in the bore. Also the tube has the Invector-Plus long taper choke tube technology and is Made for barrels designated as 20 gauge Invector-Plus ONLY.