Easy no gunsmith install, all tools included. Allows the user to mount an optic and a light or laser while retaining the factory handguard. Forward M-LOK slot allows mounting of additional accessories. Patent pending rock solid design. Constructed of 6061 aluminum, hard coat anodized for a lifetime of service. 100% Made in the U.S.A., 922R Compliant. This rail is designed to fit 9mm receivers, there may be fitment issues with the 40cal/10mm receivers. Fits HK MP5K & SP89