I have to say I love the balance of this thing. Black Hole Weaponry 20" barrel 1:8 Twist/rifle gas .264LBC Type 1. 15" Matrix Arms "Victor Keymod handguard." SS gas tube / Lantac low gas block. SAA Forged upper. PSA Forged lower with set screw "takes out slop of upper to lower." PSA logo full-auto bolt carrier w/9310 Grendel bolt. 2lb. Hiperfire 24C trigger. Magpul Moe SL grip/stock. Primary Arms scope mount. Vortex Strike Eagle BDC 1x6.