Sig Caliber X-change Kit MCX, 5.56 NATO, 11" Barrel, Bolt Out of stock. Check back later... $612.00 MSRP Price: $575.00 Notify me when this item is back in stock (log in required) Description Details Reviews Shipping info UPC: 798681553150Manufacturer: Sig SauerModel: CALX-MCX-11B-556Caliber: 5.56x45mm NATOCategory: Conversion KitPartsOtherStock: 0Unit/Measure: ea This item may be shipped directly to your home address, unless you live in a restricted state.