The B-22 railed platform mounts on the B-21M, B-10M, B-10U, B-30U, and B-30 above the rear sight. It uses the slots at the rear of these handguards, so installing the B-33 at the same time with the B-22 is impossible.The B-22 is raised over the rear sight and does not interfere with its operation. 

B-22 Platform