A3 Industries w/Magpul #2 Butt-Pad Aluminum Butt-Plate. All butt-plates are machined from 6061 aluminum. BP3 and BP4 both have sling mounting quick disconnect sockets. Specifications for A3 Industries Aluminum Butt-Plate: Manufacturer: A3 Industries Color: Black Gun Model: Universal Fabric/Material: 6061 Aluminum Quantity: 1 Finish: Black Anodized Features of A3 Industries Aluminum Butt-Plate High-grip cushioned Magpul rubber butt-pad Quick-disconnect steel sling mounting socket Package Contents: A3 Industries Aluminum Butt-Plate QD Sling Mounting Socket What firearm models does the manufacturer say A3 Industries Aluminum Butt-Plate is compatible with? The manufacturer suggests that A3 Industries Aluminum Butt-Plate is compatible with UniversalA3 Industries BP4: w/Magpul #2 Butt-Pad Aluminum Butt-Plate