- SIG SAUER style folding stock installs easily on your MCX / MPX via the receiver's 1913 picatinny interface. - Color : Black - Material: 7075-T6 Aluminum - Length:    9.6 in - Weight:    13.4 oz - Gun Model: SIG MCX, SIG MCX-SPEAR, SIG MCX-SPEAR LT, SIG MPX