Daniel Defense 0100408001 M4A1 RIS II Handguard 12.25" 2-Piece, Free-Floating Style Made of 6061-T6 Aluminum with Flat Dark Earth Anodized Finish & Picatinny Rail for AR-15
The Daniel Defense Rail Interface System (RIS II) was designed at the request of the United States Special Operations Command (SOCOM) for the SOPMOD II program. It allows the individual operator to free-float the M203 grenade launcher without additional parts.