The Sig Sauer MCX Conversion Kit transforms your Mil-Spec AR-15 Lower Receiver into an adaptive and modular Sig Sauer MCX. The MCX Conversion comes complete with the Sig MCX Upper Receiver Assembly with M-LOK Handguard, Lower Receiver Stock Adapter, Side-Folding AR Buffer Tube Knuckle, and Sig Duo Trigger.

Due to high demand and our desire to serve as many Customers as possible, we are currently limiting the quantity that each individual Customer may order.

One Time Offers represent special one-time purchases where MidwayUSA has negotiated a reduced price and then passed the savings on to the Customer. One Time Offers have limited quantities available and usually once they are sold out, they are not offered again.

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