TRUGLO Magnum Glo-Dot Xtreme Magnet Mount 1/4 Sight, Red Each model easily snaps over rib without need for screws. Fiber diameter is .060". 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. Endorsed by Ducks Unlimited.