BASTION Laser Engraved Rear Cover Slide Back Plate for Smith & Wesson S&W M&P Shield 9mm .40 ONLY - Widow Maker Compatible with Smith & Wesson M&P 9mm SHIELD Model ONLY Is NOT compatible with SW MP 9mm full/compact models or new .45 model. Hard coat anodized T6 machined aluminum Lasered artwork won't rub off; not painted Does Not Fit Compact or Full Size models including new .45 model