The Smith & Wesson M&P40 Shield is a slim, striker-fired subcompact pistol chambered in .40 S&W, designed for concealed carry. It features a 3.1-inch barrel, 6.1-inch total length, and a width of approximately 0.95–1 inch, with an unloaded weight of 18.1–19 oz. It typically includes 6-round flush and 7-round extended magazines. 
Key Specifications
Caliber: .40 S&W
Barrel Length: 3.1 inches
Overall Length: 6.1 inches
Height: 4.6 inches
Width: 0.95 - 1.0 inches
Weight (Unloaded): 18.1 - 19 oz
Capacity: 6+1 or 7+1 rounds
Action: Striker-fired
Frame Material: Polymer
Slide Material: Stainless Steel with Armornite/Melonite Finish
Sights: Fixed White Dot (standard)
Safety: Manual Thumb Safety (optional, available on some models) 
Smith & Wesson +8
Features
Grip: 18-degree angle with aggressive texture (M2.0 models)
Trigger: Consistent pull, approximately 6.5 lbs, with a tactile/audible reset
Magazines: Includes a flush-fit 6-round and an extended 7-round magazine
Disassembly: M&P patented take-down lever (no trigger pull required)