This adapter and 8.5" rear stock combination features an open design that is lightweight and offers a great line of sight for using iron sights or a rail mounted scope. Stock and adapter weigh 1.1lbs. Length with adapter is about 8". New grip block on the underside of the adapter for added strength to secure the grip. Adapter fits between the receiver and the grip, machined to fit around the receiver for added strength. We include two grip bolts for use with the OEM grip and most aftermarket grips. *This part number includes polymer 8.5" rear stock, stock adapter and 2 longer grip bolts.