The PR-4 Carbine Sling Mount installs on any M4-style carbine receiver extension” with no weapon disassembly required. It provides a perfect ambidextrous and rear facing anchor location for single-point or other types of tactical slings. It’s great for Agency or Department use” if no ‘permanent modifications’ are allowed. Installs and removes in minutes. Smooth shape does not interfere with charging handle or weapon manipulation. Perfect for in-vehicle use” and rapid side transitions. Installation tool and heavy-duty push button sling swivel included. Fits M4″ MK 18″ AR-15 carbines” MIL-SPEC and commercial diameter receiver extensions. Sling NOT included.