Built to handle the powerful .357 SIG round this factory 9-round magazine for the Glock G33 offers the reliability and durability you expect from OEM Glock gear. Constructed with a tough polymer body full-length steel inserts and numbered witness holes it's engineered to fit flush and perform flawlessly in Gen 3 4 and 5 Glock 33 pistols.Glock G33 .357 SIG OEM Magazine - 9 Round (Black Polymer)Fits Gen 3 Gen 4 and Gen 5 Glock 33 pistolsFull-length steel inserts for added strengthNumbered witness holes for easy round trackingDurable polymer body built to endure tough conditionsThese factory mags are known for their strong spring tension which may feel stiff during initial use. After a few load/unload cycles the spring softens slightly for easier handling-without compromising reliability. Whether you're training carrying or adding backups to your setup this Glock magazine is built to keep your .357 SIG running strong.Browse our entire Glock Magazine category!Shop for a new pistol!