This rear bag rider is compatible with any typical pinatinny rail, which makes it perfect for many different kinds of stocks, chassis and buttstocks.
I installed this on my AR10. It required removing the butt pad and installing it on the Picatinny rail. I only gave it 4 stars as the slope angle is not enough for the Luth AR stock.
Very quick turn around on shipping, the Bag rider fits great on my Luth-Ar MBA-3 very nicely made. Highly recommend
It is a great bag rider if you’re ok with it not being flat. It will work with a Caldwell rear bag. But if you have a bag designed for a flat stock. Then this isn’t the one you want. Hopefully will be offered in the future flat as well as angled.