16 Inch 12.7×42 Complete Mlok Upper
Enlarged Upper Receiver with Forward Assist and Dust Cover
15″ Mlok Rail
49/64-20 Spiral Fluted Flash Hider
16″ 12.7×42 Mag-Phos Barrel
.936 Shoulder, Carbine Gas System
1:14 Twist Rate
This does come with a FA Bolt Carrier Group and Standard Charing Handle.
You may need a heavier buffer to have this upper function reliably.
A 12.7×42/50 Beowulf Magazine will also be needed