BASTION Laser Engraved Rear Cover Slide Back Plate forSmith & Wesson S&W M&P 9mm .40 40 Cal .357 45 ACP Full Size ONLY - Widow Maker Compatible with S&W M&P 9mm, .40, .357, .45ACP Full size and Compact ONLY Including New Model 2.0 Is NOT compatible with SW MP Shield model Hard coat anodized T6 machined aluminum Lasered artwork won't rub off; not painted Replaces factory plastic part