Mission First Tactical EXD Free Float M-Lok Rail - Boasting multiple improvements, the new EXD Free Float M-LOK Rail System is designed with the modern shooter is mind. Streamlined and user-friendly, the updated design allows shooters more time to send rounds down rand and less time making field adjustments or modifications. In addtion, the upgraded upper receiver attachment system increases shoorter stability and also minimizes the inner diameter, providing a more streamlined appearance. Updated modern wall thickness addesses the flisiness of other rail systems by providing the strength needed to attac a variety of M-Lock accessories. 7 sides of M-LOK Anti-rotation technology IR anti-reflective coating Steel non-timing barrel nut Ultra streamlined appearance