Smith & Wesson increased scrutiny due to the frequent use of its firearms in mass shootings such as the 2018 Stoneman Douglas High School shooting, in which 19-year-old Nikolas Jacob Cruz used a Smith & Wesson AR-15 style rifle, the semi-automatic M&P15. The same weapon was used in the 2015 San Bernardino attack and the 2012 Aurora shooting. Smith & Wesson has produced revolvers over the years in several standard frame sizes. "M" refers to the small early Ladysmith frame, "I" to the small .32 frame, "J" to the small .38 frame, "K" to the medium .38 frame, "L" to medium large, and
Smith & Wesson SD series and the Smith & Wesson M&P design. Smith & Wesson SD The Smith & Wesson SD, formerly known as the Sigma, was Smith & Wesson's first venture into using synthetic materials in pistol construction, using high-strength polymer material for the frame. The pistol is similar to a Glock safe-action pistol in both its design and operation, leading to some controversy and speculation as to the legality of the pistol's patents. Created in 1994, the Sigma incorporates pre-set striker firing mechanism. It is available in both .40 S&W cartridge and 9×19mm Parabellum being one of the first pistols purpose-designed to