Sig Sauer MCX Rattler .300 Blackout complete upper receiver with AR conversion kit. This Sig MCX Rattler upper has a 5.5" PDW barrel and a free floating M-LOK handguard to make it the most compact, agile upper receiver available. This kit comes with the complete MCX upper receiver, adapters to convert a standard Mil-Spec AR15 lower receiver so it's functional with the upper, and Sig's Match Duo 2 stage trigger, everything needs to remove your current AR rifle upper and upgrade to the MCX easily.
Part Number: SMCXRC-BLK
Out of Stock.