The wide construction of the NEMO 556 handguard provides superior heat shielding as well as the ability to accommodate custom builds with suppressors. – Caliber: 5.56 NATO – Height: 1.216 in (bore centerline to top of rail) – Length: 15 in – Exterior Width: 2.22 in – Inner Diameter: 1.83 in – Large inner diameter accommodates many under guard suppressors (1.83 in) – M-LOK™ slots at 36 and 9 o’clock positions accept M-LOK compatible accessories. – Integrated rail at 12 o’clock with engraved T-marks – 6061-t6 aluminum alloy extrusion – Mil-Spec hard anodize type 3 (black) – Integrated rotation limited steel quick disconnect sling mounts – 7075-t6 aluminum barrel nut type 3 hard anodize (1.25-18 thread) – Innovative mounting system provides a rigid and lightweight solution – Stainless steel fasteners and retainers ensure corrosion resistance – Utilizes a common T-15 wrench (Not Included) – Purple thread locker recommended (Not Included)