The leapers MNT-BR003XLS UTG universal single-rail shotgun barrel mount with 3 Slots is compatible with shotgun barrels and magazine tube diameter between 75"-1.1" inches around. Shotgun barrel mount with picatinny/weaver style rail is solid aluminum construction with matte black finish. Easy to install 2 piece design for clamping to shotgun barrels, magazine tube extension and lets you mount laser sights, tactical flashlights or bipod.