ProMag SMIA11 S&W M&P 40 .40 S&W Magazine 15rd Blued Steel

The ProMag SMIA11 is a .40 S&W 15-round double-stack detachable pistol magazine purpose-built for the Smith & Wesson M&P 40 series of handguns. Constructed around a heat-treated steel body finished in black oxide, this magazine delivers the durable, wear-resistant build that has made ProMag a go-to source for affordable spare and replacement magazines.

Inside the steel housing, an injection-molded polymer follower pairs with a chrome-silicon wire spring to keep rounds stacked consistently and feeding smoothly through the action. The double-stack geometry mirrors the factory M&P 40 magazine pattern for drop-in reliability on M&P 40 series pistols. The blued/oxide surface treatment protects the steel from corrosion during regular range use and long-term storage.

Whether you are topping off a duty rotation, replacing a worn factory unit, or building out a dedicated training loadout, the SMIA11 provides a dependable 15-round feeding solution for your .40 S&W M&P pistol.