This picatinny bottle clamp is designed to fit the BSA R12.
The mount slides onto the bottle and is tightened using a single bolt, the rubber pads allow for a very tight solid fit on your bottle it will not move once tightened.
It has a single 45mm picatinny rail allowing you to attach a bipod/torch Etc.
Plus 74mm square bench rest block with female picatinny slot.