Designed by Bill Wilson and the Wilson Combat design team to be the base for the ultimate precision tactical AR-10 rifle, the BILLet-AR upper is 100% machined in our Berryville, AR facility.The Wilson Combat BILLet-AR-10 receiver set was engineered from the ground up to address structural design weaknesses in standard receivers and enhance overall tolerances which improve shot to shot consistency.The BILLet-AR upper receiver has a precise bolt raceway for smoother chambering and more rigid receiver walls to reduce firing flex. This receiver has been lightened for the lowest weight possible.Our extensive experience as a premier custom builder of AR rifles will ensure your satisfaction with this next generation precision tactical shooting platform.NOTE: This upper is only compatible with Wilson Combat WC-10 lower receivers.CNC machined from 7075-T6 aerospace aluminum billet stock with Type 3 Anodized finish.Picatinny top rail.Shell deflector.M4-style extended feed ramps for excellent reliability with a wide variety of calibers.Undersize bolt raceway for smoother chambering, improved feeding, and enhanced recoil dynamics.Lightened side profile without forward assist, perfect for hard use.Hand prepped for a flawless surface finish.Approximate Weight, 9.8 Oz.