F HECKLER AND KOCH MR556 UPPER RECR KIT $1,618.99 81000584 show more like this Calculated in cart GunZoneDeals F HECKLER AND KOCH MR556 UPPER RECR KIT $1,680.67 81000584 show more like this Free shipping over $400 (Excludes Ammo) Gman Sport F HECKLER AND KOCH MR556 UPPER RECR KIT $1,681.44 81000584 show more like this Free on Firearms Acute Firearms F HK MR556A1 UPPER RECEIVER KIT 223 REMINGTON/556NATO 16.5" COLD HAMMER FORGED BARREL $1,689.00 81000584 show more like this 14.95 TheGunDock.com F HECKLER AND KOCH MR556 UPPER RECR KIT $1,730.23 81000584 show more like this Huligan Arms F HECKLER AND KOCH MR556 UPPER RECR KIT $1,781.35 81000584 show more like this Free shipping on orders over $300 Skogen’s Gun Supply F Heckler & Koch Mr556 Upper Receiver Kit 16.5" Medium Contour M-Lok 81000584 MAP 81000584 show more like this Firearms $18.45, Free over $500 Shooting Surplus