The receiver mounting scheme of our receiver mount shotgun SureShell shotshell carriers for the Mossberg 500/590 substitutes a steel bolt for the trigger pin retained in place by a black oxide plated acorn nut. At the front of the mounting plate, custom retaining steel hardware is used with an elongated extractor screw and a machined key hole In the plate. The mounting plate was designed not to obscure the receiver serial number to make it easier for armorers to inventory their weapons.
SureShell shotshell carriers for the Mossberg fit on the left side of the receiver only. You must use a tactical forend that does not significantly overlap the receiver, or a factory forend that is cut down appropriately. SureFire forends will work fine with no alterations.