This threaded, front bead replacement, Spark III shotgun sight is interchangeable style, and includes red, white, and green, fiber optic family LitePipes. Each Spark III 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 a removable front bead. The Litepipe Diameter is 0.090 inches, and the overall height is 0.160 inches.
Replacement LitePipes for this sight can be foud here.
HiViz Shooting Systems by North Pass Ltd
1941 Heath Parkway #1
Fort Collins, CO 80524