Raven Concealment Systems TopStop Features The Raven Concealment Systems TopStop snaps securely onto most AR-15 or M4 pattern upper receivers once they are detached from the lower creating a protective seal over the open receiver channel. That seal keeps fouling dirt sand and other debris from entering the action while the upper sits in a range bag truck bed or gear case and just as importantly keeps carbon and lubricant from migrating out onto other equipment. Molded from tough impact resistant polymer the cover is built to handle repeated snapping on and off without cracking or losing its grip on the receiver s rails. Its high visibility yellow finish makes the cover easy to spot in a cluttered range bag or gear tote. Beyond sealing out contaminants the TopStop also physically prevents the bolt carrier group and charging handle from sliding out of the upper as it is carried or shifted around which matters for anyone transporting a disassembled rifle between a safe a vehicle and the range. This is especially useful for competitive shooters and armorers who routinely break their rifles down for cleaning maintenance or component swaps and need a way to keep the upper s internals contained in the interim. The cover s snap fit design requires no tools and installs in seconds making it a convenient addition to any range bag or cleaning kit. For anyone who regularly separates their AR-15 upper from the lower the TopStop offers simple effective protection. Raven Concealment Systems TopStop Specifications Manufacturer: Raven Concealment Systems Model: TopStop Compatible Hosts: AR-15 Color: Yellow Finish: Matte Material: Polymer Available At: GrabAGun