Strike Industries M&P 9mm/.40 Cal Magazine Plate Black One Size. It adds magazine capacity by +6 to 9mm rounds or +5 to .40 caliber rounds. It was designed to provide smoother and faster magazine reloading. Included is their special steel locking plate which compared to other magazine extensions on the market features a hook design which adds extra locking security to increase reliability when fully loaded with rounds. Specifications for Strike Industries M&P 9mm/.40 Cal Magazine Plate: Manufacturer: Strike Industries Color: Black Fabric/Material: Steel Magazine Capacity: 6 Round Caliber: 9mm Luger .40 S&W Gun Make: Smith & Wesson Gun Model: Smith & Wesson M&P Condition: New Features of Strike Industries M&P 9mm/.40 Cal Magazine Plate Durable polymer construction with steel locking plate EMP matches the look of the M&P stock grip for aesthetic appeal Designed for easy gripping for smoother and faster reloads Magazine extension +6 rounds for .9mm Magazine extension +5 rounds for .40cal Package Contents: Strike Industries M&P 9mm/.40 Cal Magazine Plate 1 M&P 9/40 EMP 1 Steel Locking Plate 1 Magazine Spring 1 M4 Set Screw What firearm models does the manufacturer say Strike Industries M&P 9mm/.40 Cal Magazine Plate is compatible with? The manufacturer suggests that Strike Industries M&P 9mm/.40 Cal Magazine Plate is compatible with Smith & Wesson M&PStrike Industries SI-EMP-MP9&40-BK: M&P 9mm/.40 Cal Magazine Plate Black One Size