Precision CNC Machined for billet 7075-T6 Aluminum" the BAD-EMMR features" unique" patent-pending three sided dovetail finger pad attachment mechanism that allows for maximum strength" an almost uninterrupted finger pad face for maximum design aesthetics" lightweight and low profile design. The interchangeable finger pads offer excellent ergonomic feel and ease of operation without shifting grip position. If you are looking for maximum flexibility" robust design" and unparalleled design aesthetics" the BAD-EMMR is the ultimate extended magazine release for you. Due to the variances in AR308 billet receivers" may not be compatible.