Eight years after Glocks original unveiling of the G21 the G21 Gen 3 was introduced. Chambered in 45 ACP with a polymer frame and a 131 capacity in a staggered-column magazine the Glock 21 Gen 3 is a semi-automatic handgun manufactured primarily for the American market. It featured a built-in accessory rail known as the Universal Glock rail thumb rests on both sides of the frame and finger grooves on the front of the grip which also had checkering on the front- and backstraps along with textured sides. Later versions of the G21 Gen 3 also featured a modified extractor that doubled as a loaded chamber indicator an enlarged locking block and an extra ross pin. DetailsG21SF 45ACP FS 131 GLOCK RAIL GLOCK RAIL STD MAG RELEASE
