This new Bushmaster XM15-E2S complete lower receiver is ready to finish your favorite AR-15 build (.223, 5.56, .300BLK, 6.8 Spl, .450 Bushmaster, 458 SOCOM, .50 Beowulf, etc). This lower has a 6 position stock and comes in a box. $ 329.00 PS HAVE A CONSECUTIVE NUMBERED PAIR AVAILABLE