http://store.troyind.com/12_MRF_CX_Extended_Sights_p/srai-mrf-c2bt-00.htm

The Troy MRF is the strongest user-installed free-floating rail system in the world. Troy MRFs are available for all M16/M4 weapon systems equipped with the original factory barrel nut. The MRF’s patented mounting system reinforces the barrel nut with a sturdy clamp and anti-rotation alignment lugs. Troy MRF BattleRails provide an uninterrupted rail extension and hand guard aligned perfectly with the host weapon's flat-top receiver. Machined from 6061-T6 hardened aircraft aluminum and finished in MIL-SPEC Type III hard coat with Teflon. Accepts Quick-Detach 360 Push Button Swivel. Made in the U.S.A. *Lifetime limited warranty, see www.troyind.com for details.

I NEED $150 SHIPPED ON THIS. PAYPUKE PREFERRED. THANKS