I have been wanting an arca rail on my br. My mpa chassis is an older model so it does not have the arca cut like my new one does. So I ordered a rail for camera equipment. It worked out great! I'm able to use the 2 thumb screws to loosen it and slide it forward when I want my bipod or tripod out farther. It's easy to remove and there are little rubber pads that protect my chassis. I did have to thread 2 holes that were already on my chassis but that was easy on my mill. It sure makes it solid with my mini tripod on the front.