The Noveske NSR (Noveske Skinny Rail) 15"" Hand Guard was designed with the goal of being the lightest and smallest free float forend option for the Modern Sporting Rifle enthusiast. If you own an AR-15 and you are concerned with creating the lightest weight load out rifle with maximum functionality"" you have found the perfect rail. The M-LOK interlocking rail system came about as a result of collaboration between Magpul and Noveske Rifleworks. The M-LOK slots allow you an almost limitless combination of mounting points without the extra weight associated with similarly sized Picatinny rails. Everyone should own at least one of these hand guards so that you can experience for yourself the M-LOK difference. Fits AR rifles.