USED Troy 7 in. Modular Rail Forend Drop in for M4/M16/AR15 Carbines Black NSN - 1005-01-644-6293 SRAI-MRF-D7BT-00. The Troy Patented Clamping design ensures absolute rock solid mounting. Troy MRF-DI provides a true optical mounting platform that increases the modularity and accuracy of the M4. No gunsmithing is required as the MRF-DI installs in less than a minute and provides true U.S. Military Specification M1913 rails at 12-3-6 and 9 o'clock. All Troy MRF rail systems are machined from hardened aircraft aluminum and finished in MIL-STD Type III Hard Coat Anodize. Specifications for Troy Modular AR-15/M4/M16 Rail Drop In Forend: Manufacturer: Troy Color: Black Finish: Anodized Fabric/Material: 6061-T6 Aluminum Gun Make: AR Platform Gun Model: M4 M16 AR-15 Gun Type: Rifle Handguard Length: 7 in Handguard Type: Drop-In Handguard Style: Quad Rail Gun Rail: Picatinny Included Accessories: Standard Country of Origin: USA Caliber: 5.56x45mm NATO .223 Remington Hand: Ambidextrous Quantity: 1 Features of Troy Modular AR-15/M4/M16 Rail Drop In Forend: Numbered cross slots; M203 Capable; Accepts 360 push button swivels (sold separately); Positive clamping provides true optical mounting platform; Installs in less then two minutes; Does not alter weapon Package Contents: Troy Modular AR-15/M4/M16 Rail Drop In Forend Troy SRAI-MRF-D7BT-00: 7 in. Modular Rail Forend Drop in for M4/M16/AR15 Carbines Black NSN - 1005-01-644-6293