This metal top rail assembly fits both the LM4 and KM4 Series, which includes the CQR Series, Commando, KM4A1, and KM16 Battle Rifle. It comes preassembled with connecting brackets and appears on the LM4 PTR diagram as 111-5,89,102. The KM4 Series diagrams will have this part listed as 266, which also comes with parts 88 and 89.  This piece will not fit the brand new LM4 PTR Series, which comes with a one-piece upper.



Weight .1 lbs
Dimensions 5 × 1 × .5 in