This is an add-on service upgrade to our premium MG-34, again, and of course, another US RGC Exclusive. What do you get?: Rear sight Notch improvement, Vintage finish Furniture, Enhanced Metal Finish to make it look even more like blued steel, and the Feed Tray is modifies to accept an Assault Drum! *Note, without this upgrade, your MG-34/42 or M53 drum will NOT fit. Also included in the upgrade package is a front and rear (Pistol Grip) sling attachment modification that will allow you to add your original Sling!