Spikes Tactical SAR3 12in Rail - The Spike's Tactical SAR3 system is a lightweight1-piece quad rail. Sharing many of the same characteristics of the appealing Spike's BAR2 rail, the SAR3 rail is even lighter. Each component is manufactured to precise tolerances for a firm fit and reliable service. 1 Piece Free Float Design Rail - 6061-T6 Aluminum Barrel Nut - 7075-T6 Aluminum Black Type III Hardcoat Anodized Built In Anti-Rotation Tabs Excellent Heat Ventilation Scalloped Rails 6 Built In Q.D. Sockets (Sling Attachment Points) Continuous Top Rail Compatible With Many Low profile Gas Blocks Barrel Nut Works with Standard USGI 3 Pin Barrel Nut Wrench Includes: (1) 12in SAR3 Rail, (3) Black Ergo Rail Covers, (1) Barrel Nut, (1) Heavy Duty Q.D. Sling Loop, (6) Barrel Nut Shims, (One .025in, One .0125in, Two .003in, And Two .0015in), (6) Grade 8 T-20 Torx Screws, (2) 3/32in Allen Head Screws (Install on Top of Rail Only), (1) Tube of Blue Loctite. (1) T-20 Torx Wrench, (1) Instruction Sheet, And (1) Spike's Tactical Lifetime Warranty