MAGNUM GLO•DOT™ XTREME SERIES Each model easily snaps over rib without need for screws.Fiber diameter is .060”.Endorsed by Ducks Unlimited.1/4” fits most Remington, Browning Gold (camo) and Charles Daly.3/8” fits most Mossberg, Weatherby, Winchester (excluding SX3) and popular 10 ga. models.6mm fits most Beretta Field Grade, Benelli 20 ga., Browning Gold / A-5, Franchi and Winchester SX3 models.5/16” fits most Benelli Browning BPS, Ithaca, Ruger Red Label, Savage and 8mm ribs. Magnum Glo-Dot sights, each model easily snaps over rib without need for screws. Ultra-tough composite construction. Fiber diameter is .060".