Sons of Liberty Gun Works AR/M4 Stripped Upper Receiver A quality upper receiver built to the demanding and exacting SOLGW is known for. (Inside Diameter for barrel extension slightly undersized for a tighter fit to the barrel and a more accurate rifle. Please use a heat gun or hair dryer to warm up threaded bore of receiver if barrel extension is too tight.) Specifications Forged from and machined from 7075T6 aluminum T marked Hardcoat anodized
