Precision Reflex .308 SPR DPMS Receiver Full Top Rail System 19 inch Black. This rail has a full 1913 rail across the top. Rails come with mounting screws for attachment to forearm rail. The rail is 19in in length. Add .475in to the elevation of the receiver. There are 3 cross bolts that tie the top rail to the receiver and 4 #10-32 socket head screws and a bar nut that secures top rail to forearm. Top rail is designed to work with PRI round 308 forearms. This forearm is designed to work with DPMS low receivers or receivers that are 1.253in off bore center to top of receiver. Specifications for Precision Reflex .308 SPR DPMS Receiver Full Top Rail System: Manufacturer: Precision Reflex Color: Black Finish: Hard Coat Anodized Fabric/Material: Aluminum Cant: 0 MOA Gun Make: AR Platform Gun Model: AR-10 Length: 19 in Width: 1.325 in Height: 0.475 in Weight: 12.7 oz Condition: New Features of Precision Reflex .308 SPR DPMS Full Top Rail System: Rail is constructed of T6 6061 hard coated black anodized aluminum This rail has a full 1913 rail across the top Rails come with mounting screws for attachment to forearm rail The rail is 19" in length Add .475" to the elevation of the receiver There are 3 cross bolts that tie the top rail to the receiver and 4 #10-32 socket head screws and a bar nut that secures top rail to forearm Top rail is designed to work with PRI round 308 forearms This forearm is designed to work withDPMSreceivers or receivers that are 1.253" off bore center to top of receiver. Package Contents: Precision Reflex .308 SPR DPMS Receiver Full Top Rail System Precision Reflex 03-072-SPR-D: .308 SPR DPMS Receiver Full Top Rail System 19 inch Black