When polymer wont work, Magpul s AMAGs will. The same reliability and consistency you expect out of our PMAGs , now available in alloy magazines. The AMAG 17 SG9 is a 17-round SIG P320 9mm handgun magazine featuring a heat-treated, stainless-steel alloy body with polymer sub-components. Magpul AMAGs come with many of our proven features, including a high-visibility, controlled-tilt follower, stainless-steel spring, flared floorplate that s easily removable for cleaning and routine maintenance, paint-pen dot matrix for magazine marking, and capacity-indicator windows which begin at five (5) rounds, and continue along the spine of the magazine in one-round increments. Made in the USA. Product Specifications Caliber: 9x19mm Parabellum Platform: SIG P320 /M17 Capacity: 17 rounds Materials: Heat-treated, stainless-steel alloy body and spring with polymer floorplate and follower Weight: 3.2 oz / 89 g Compatibility: The AMAG 17 SG9 is compatible with full-size, compact, and sub-compact variants of the SIG P320/M17/M18 platform