The Spark II is one of the first compact sights that HIVIZ developed and remains a top seller today. Its tiny but brilliant with an affordable price tag. Unlike the Spark III, the LitePipes are not interchangeable, so make sure you pick the color that best suits your needs. Fits most vent-ribbed shotguns with removeable front bead. Sight includes five screws in varying thread sizes to fit nearly any shotgun: 3-56"; 5-40"; 6-48"; 3mm x 0.5; 3mm x 0.6.