Looks pretty complicated and the pictures seem to show it has to attach at one point through the trigger pin.
I like the notion of the red laser pointers mounted on the bottom rail but the ones I have tried are not very stable, I think partly due to instability of the plastic rail. If anyone has found a stable pointer I'm open for another test.
================
Well, maybe I'm being too strict. The pointers I have tried have drifted only 6-8" at 20'. That's good enough for me.