Up for sale is a factory original SIG Sauer MCX Pistol Lower Receiver. The lower is in Great Condition
For sale is a SIG Sauer MCX pistol lower receiver — the serialized half of an MCX pistol build. This is an SIG MCX lower, not a standard AR-15 lower. It is made for the SIG MCX / MCX Spear LT family and pairs with a matching MCX upper.
The MCX lower is what gives the platform its folding-stock or brace flexibility. There is no conventional AR buffer tube in the same way as a rifle-length AR-15, so this receiver is the right foundation for an MCX pistol, SBR (NFA, if registered), or folding setup. Ambidextrous controls and SIG’s MCX fire-control layout are the point of buying a factory lower instead of a mix-and-match AR part.
Listing notes
If you are searching for a SIG MCX PISTOL LOWER. This is the one
