Geissele Automatics MK4 Super Modular Rail "Federal" 10" M-LOK Handguard (AR15/M4)
The Geissele MK4 "Federal" 10" Super Modular Rail is a free-float AR15/M4 handguard built from 7000 series aluminum with a Type 3 hardcoat anodized finish. This Federal-variant rail features M-LOK slots at the 3, 6, and 9 o'clock positions plus the upper 45° quadrants, along with integrated M1913 Picatinny sections at the fore of the rail in the 3, 6, and 9 o'clock positions (with an elongated 6 o'clock section).
Designed around mil-spec M4 upper receivers, the MK4 provides a rigid mounting platform while keeping weight down through extensive venting. Barrel nut is present.