Kalashnikov USA's Eastern Bloc K-21 M-LOK Rail & Fore-end System is the perfect upgrade to the KR-103 or KP-9/KR-9 series of rifles and pistols. It replaces the original polymer/wood fore-end, and installs quickly and easily. Once installed, it provides a wide range of customization options thanks to multiple M-LOK slots and picatinny rails. These attachment points can be used to mount accessories such as tactical lights/lasers, vertical grips, and forward-mounted optics.