Raven Concealment Systems TopStop Features The Raven Concealment Systems TopStop snaps directly onto most AR-15 or M4 type upper receivers once they have been detached from the lower sealing the open rear of the upper against fouling and debris. This closure prevents dirt and contaminants from entering the receiver during cleaning storage or transport between range sessions. The cover also physically stops the bolt carrier group and charging handle from sliding out of the upper while it is being moved or handled separately from the lower. This keeps internal components contained and reduces the risk of losing or damaging parts during disassembly. Molded from tough polymer the TopStop is lightweight yet durable enough to withstand repeated snap on and snap off use without cracking or losing its grip on the receiver. Its matte Wolf Gray finish gives it a low profile appearance that will not draw attention in a range bag or gun case. The TopStop is built specifically to fit uppers that are detached from the lower receiver so it is a natural fit for builders armorers and owners who regularly break their rifle down for deep cleaning or storage. For anyone looking for a simple way to protect a detached AR-15 upper the Raven Concealment Systems TopStop is available for sale at GrabAGun. Raven Concealment Systems TopStop Specifications Manufacturer: Raven Concealment Systems Model: TopStop Type: Storage Color: Gray Finish: Matte Compatible Hosts: AR-15 Uppers Available At: GrabAGun