DPMS Evolution Series 12.5The DPMS Evolution Rail is an adaptation of our popular Evolution Series Rail. This rail is built specifically for the DPMS LR308 receiver geometry. Included is a modified DPMS barrel nut which is required for installation. Kit includes (2) 2 " accessory rails (1) 4 " accessory rail and all mounting hardware. No thermal bushings are required for installation. Will fit any .308 upper receiver with new DPMS low profile receiver height (ie S&W M&P10).Rifle LengthFree Float Design303 Stainless Included DPMS barrel nutRelieved for Most Gas Piston SystemsNo Need To Remove Front Sight BaseRail Includes Integrated Anti-Rotation TabsAll Rails 1913 Picatinny Mil-SpecType III Mil-Spec Hard Coat AnodizingPrecision Laser EngravingForms Continuous Top Rail6061 T6 AluminumOverall Length: 12.5 "Measurement from center of bore line to top of picatinny rail - 1.253 Thread - 1 7/16 -16 TPI-2AWeight: 11.5 ozID: 1.56 "OD: 1.8 "