Red laser with constant beam; Custom designed to fit the S&W M&P Shield 9mm, .40 cal; Mounts to the frame without changing out parts or altering your weapon; Sits just under the bore for highest accuracy and prevents your finger from blocking the beam; Controlled Activation for right or left-handed shooters; Distinct On/Off switch turns the laser on only when you need it; User installed in minutes; Black finish; 5 year manufacturer warranty