RIS II M4A1 Upper Receiver 14.5 Pinned and Welded 5.56 (16” OAL) Flat Dark Earth Warden Features Optimized for rifle-length receiver

Features Optimized for rifle-length receiver extensions

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RIS II M4A1 Upper Receiver 14.5 Pinned and Welded 5.56 (16” OAL) Flat Dark Earth Warden Features Optimized for rifle-length receiverThe Daniel Defense M4A1 Upper Receiver Group features the M4A1 Rail Interface System (RIS II), which has been in use by US Special Operations Command (SOCOM) for the SOPMOD II Weapons System since 2005. This two piece, free floating rail system allows the mounting of devices like a M203 grenade launcher without influencing the barrels harmonics, eliminating problems like wandering point of impact that plagued other mounting designs. The two piece