Please be advise this is actually M-LOK! Even though picture shows Keymod.
The Radical Firearms M4 Upper Receiver is a flat top, law-enforcement grade, drop in receiver, ready to be mounted to any Mil-Spec AR-15 lower receiver! This fully MIL-STD receiver provides a high-quality upper for any level budget or shooter. Comes complete and assembled with Upper Receiver, Forward Assist, Ejection Port Door, RF Barrel Nut. 20" 6.5 Grendel Complete Upper comes with a Stainless Steel Barrel and Pepper Pot Brake. Our free-float handguard: First-Gen Hybrid Rail (FHR) keeps your hands cool and provides plenty of room for accessories. The FHR rail even has the capability to add attachments other than on the top picatinny rail, as it does allow keymod attachments and rail sections on the sides and bottom of the rail. This is a complete upper including Bolt Carrier Group and Charging Handle.
- 20” 416R Stainless Steel Barrel
- 6.5 Grendel
- 1:9 Twist Rate
- M4 Feed Ramps
- Low Profile Gas Block
- Rifle Length Gas System
- Forged MIL-STD Upper Receiver
- MIL-STD Upper Parts Kit
- BCG With Melonite Coating
- MIL-STD Charging Handle
- Radical Firearms 15" Free Float FHR (First-Gen Hybrid Rail)
- Quad Picatinny Rails on all four sides for at the fore end of the rail for mounting Lights, Lasers, Bipods & Sights
- M-LOK accessory slots on the sides and bottom to accept accessories
- Custom Radical Firearms Pepper Pot Brake