GMG AR15 Quad Rail with Forward Extension, GM-QRE1: * Locks firmly in place when tightened * Eliminates any hint of side-to-side slop * Notches run the full length of the rail in order to provide extra strength and rigidity * Eliminates any flex or torsion in * Provides a stable mounting platform * Capable of maintaining 0 on even the finest of optics * Solid aluminum 2-piece construction * Black anodized * No gunsmithing necessary * Provides additional rail mounting in front of standard carbine sight