F Aero Precision M4E1-E EM16.6 Complete Upper, .223 Wylde, 18inch, SPR, Rifle, 1-8 Twist, 1/2 x 28 Thread, Anodized, Black, APAR600220M76 $639.99 APAR600220M76 show more like this Free Shipping on most orders over $49 Optics Planet