Upgrade the performance of your AR15 build with this 6.5 Grendel Complete Upper Receiver. Designed to be a low recoil/high accuracy cartridge, the 6.5 Grendel is ideal for those looking to stretch the legs of their AR15 rifle, with proven results at 1000+ yards. This complete upper includes Aero Precisions new ATLAS R-ONE Handguard! The R-ONE handguards are designed with size and weight in mind, while still providing plenty of real-estate to accommodate any attachment needs the end user may have. Aero Precisions proprietary ATLAS attachment system is a durable and dependable mounting platform, maintaining a slim profile while still providing the strength and stability customers have Mfg: Aero Precision