Fits: Fits: G21 Gen3 and Gen4 M16 X 1 LH .45 Auto Metric Threaded Barrel w/Metal Thread protector (PKG) While supplies last.
*Not compatible with G21 Gen5
Note: Threaded barrels are defined as “assault weapons” pursuant to the laws of California, Connecticut, Delaware, District of Columbia, Illinois, New York, and Washington and may not be sold to commercial customers in these states.
