4140 Heat Treated Barrel Nut Barrel Nut and Wrench Included Features Patented 4140 Heat Treated Torque Plate 9.50" overall length 8.3 oz Installed Weight 6061 Aluminum Type 3 Hard Coat Anodized Continuous MIL-STD 1913 Picatinny Top rail Two Integral Anti-Rotation QD Sling Sockets Super Slim 1.5” Outside and 1.3” Inside Diameter Seven Sides of M-Lok 5-Slot Polymer M-Lok rail included Fully Dehorned and Deburred 100% Made in USA- Keeps America Working MI Lifetime Warranty Optional Titanium Barrel Nut and Titanium Clamp Screws Available for PurchaseIMPORTANT COMPATIBILTY NOTES!Due to the many different dimensions in BILLET UPPER RECEIVERS on the market, please contact your billet upper receiver manufacture to insure fit of this handguard. This handguard is compatible with forged upper receivers as well as the Midwest Industries billet upper receiver.NOT FOR USE ON GAS PISTON AR’s!Magpul(R) and M-LOK(TM) are trademarks of Magpul Industries Corp