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Pin for MR556 and MR762 hammer and trigger

Firing pin retainer spring for MR556 and MR762 rifles

Originally designed for the US military’s SOPMOD rifle enhancement program, the KAC M4 Folding Front Sight is a low-profile backup sighting solution that is designed to be attached to the top rail of a rifle’s handguard. When stowed in the folded position, the M4’s sight base extends back to envelope the front sight leaf on the right and left side, helping to protect it from damage.

Detent for MR takdown pins

Trigger fuard pin for MR rifles

Castle nut wrench for MR556 and MR762 rifles.

Spring for MR takedown pins

Clamping sleeve for buffer locking pin