Glock has built a reputation for building hard use quality firearms and accessories. The Glock MF17033 9mm 33rd extended magazine is made with the same standards as the regular capacity magazines. Steel liner with a super tough polymer coating, the steel liner provides a rigid frame so the spring tension won't cause the polymer to bulge. While the polymer coating adds the protection of scratch and impact resistance that Glock pistols and magazines have been known for. The 33rd extended 9mm Glock magazine will fit any double stack 9mm from the subcompact 26 to the Practical/Tactical 34 and will fit most generations of Glock pistols.