Aspect mounted program using an integrated MILSTD 1913 rail piece for sighting methods. Suitable for use with the M203. only one details level, I picked up a few salty made use of P&S M4 RAS's from Thoroughbred for $a hundred and fifty ea. yeah, not KAC, but sufficient for me. https://jaredeqjve.newsbloger.com/30064291/fascination-about-m4-ras-rail