Replaces all of the lower internals...setup using SON time on your eblade, then velocity adjustment via inline reg.
No cocking rod required, not that you would care...you will have to trim the end of your bolt pin, as it doesnt need to enter teh lower tube, to cock teh hammer anymore...36 BPS full auto tested, gun hardly even moves...if it was dark, you would have to shoot paint at something noisy, to even know it was going off!