The Aero Precision Minimal Optical Deflection (MOD) 4 handguard seamlessly blends robust construction with an ergonomic form factor ensuring no compromises between the two. Machined from 6061-T6 aluminum the handguard is engineered with a focus on stiffness to drastically reduce deflection under load. It attaches to the upper receiver via a steel barrel nut which also serves to significantly reduce point-of-impact shift when using an infrared laser aiming device under load. – In addition to its premium engineering the MOD 4 handguard offers several quality-of-life improvements. A full-length 7-sided M-LOK interface allows the user to customize their build according to their preferences. The steel-reinforced QD sockets are a small but important detail enhancing the sheer strength of the sockets and ensuring they do not wear prematurely when interfaced with standard steel QD sling attachments. Installation of this handguard is simplified at the barrel nut as the need for timing has been eliminated and the barrel nut lug pattern matches mil-spec castle nuts removing the need for specialty tools. Finally the inclusion of two anti-rotation set screws adds redundancy and ensures a more tailored fit when the handguard is used with third-party upper receivers. – Features: – 6061-T6 aluminum construction – Steel barrel nut – 7 sided M-LOK – 4 steel-reinforced Quick Disconnect (QD) sockets – Internal Diameter: 1.2 – Compatible with low-profile gas blocks – Includes: – 12.7 MOD 4 Handguard – Anodized Black Finish – MOD 4 Barrel Nut – MOD 4 Mounting Hardware – NOTE: MOD 4 Handguards are designed to match seamlessly with our M4E1 Threaded Upper Receivers and components from the PRO series. Additionally the MOD 4 handguards are compatible with Mil-Spec AR-15 upper receivers.