I have a few KAC M5 Rail systems for the long version of the AR-15. The us GOVT(Army and Marines use them on quite a few of the M16's)
They are brand new. Come with a bag with rail rib covers and a KAC forward grip.
http://www.knightarmco.com/portfolio/m5-rifle-ras/ is Exactly what they are and look like.
The price is in the title, but I keep getting the question, they are 110 USD shipped.
As my feedback shows, I know what im doing. Paypal only please. I might take a USPS MO if 100% necessary. I check PM's about once a day, but will get emails more often.
I also have one carbine length one but it's used and only comes with the 2 rail pieces...