The Raven TopStop upper receiver cover provides essential protection for AR15 and M4 type upper receivers when detached from the lower receiver featuring tough polymer construction and a secure snap-on design.Raven TopStop Upper Receiver CoverCompatible with most AR15 and M4 type upper receiversCompletely seals upper receiver to prevent fouling ingress and egressPrevents bolt carrier group and charging handle from sliding out during transportDurable polymer construction for long-lasting protectionEasy snap-on installation (upper must be detached from lower)Essential for firearm maintenance transport and storage this cover ensures your upper receiver components stay clean and secure while providing complete protection against contamination.