This suppressor cover fits Mac Bros MB556FAL 1.5" x 8" suppressors. The Armageddon Suppressor Cover significantly reduces and delays the effects of suppressor mirage, ensures no contact areas between nylon shell and hot suppressor, its highly-secure design stays in place, even during vigorous movements, and its adjustable shock cord ensures a custom fit. For use on bolt-action and semi-automatic precision rifles. Not to be used with fully-automatic weapons.