This is a threaded, front bead replacement, Spark II shotgun sight. Each Spark II is packaged with five threaded studs (6/48, 3/56, 5/40, 3mm x .5, and 3mm x .6), to fit most common shotguns with removable front beads. The sight's body is made of steel, with a LitePipe viewing end diameter of 0.110 inches.
These are the preferred bead for KA-1212 and KA-1212BR equipped shotguns. For installation on KA products, use the 6-48 stud.