The M4LE .22 LR Caliber AR-15 upper maintains compatibility with all the same parts and accessories that fit your full caliber AR's, including the lower receiver.
Comes with non-functional forward assist plug.

Specifications and Features:
Black Phosphated .22LR Action
16 inch W.A.S.P. steel barrel
1:16 inch twist
Mil-Spec 1/2x28 threaded muzzle
Carbon Steel Barrel
F marked Triangle Front Sight
Live Round Extraction
Anti-Jam Charging Handle
Firing Pin retained by standard AR15/M16 Cotter pin
Mil-Spec M4 Receiver with Ceramic Finish
Gas Deflector
A2 Flash Hider

UPPER DOES NOT INCLUDE MAGAZINE