This is a rare, prototype experimental version of the Colt ACR 5.56mm machine gun. It is ACR roll marked with an X marked serial number from Colt (X27754), designating it as a Colt experimental version. It utilizes the ACR pistol grip, handguard (including the white, quick acquisition stripe on the top of the handguard), and butt stock design. It also features a rare, flip up sight built into the upper receiver, that is housed underneath the removable carry handle. The ACR has the ability to use 5.56mm duplex rounds, and the listed price will include 500 rounds of factory ammunition in various designs. This machine gun is fully transferable. For more information on this listing or to view our other NFA and investment grade firearms, please visit our website at www.chestercountyarmory.com, or contact us via the information listed below. Chester County Armory West Chester, PA email: chestercountyarmory@gmail.com phone: 610-235-6155 www.chestercountyarmory.com