Griffin Armament DUAL-LOK 2.25in Stealth Flash Hider 7.62x39mm QPQ Nitride Black. The DUAL-LOK system is comprised from two parts the DUAL-LOK Mount and the DUAL-LOK muzzle device (of your choice). Specifications for Griffin Armament DUAL-LOK 2.25in Stealth Flash Hider: Manufacturer: Griffin Armament Color: Black Finish: QPQ Nitride Fabric/Material: 17-4PH Stainless Steel Length: 2.34 in Outer Diameter: 1.07 in Weight: 3.3 oz Diameter: 0.93 in Features of Griffin Armament DUAL-LOK 2.25in Stealth Flash Hider Utility patent pending Wear free mounting system requires no consumable parts Anti-Resonance flutes to prevent pinging under fire Taper lock interface ensures security and accuracy 120 effective positions ensure a rock-solid suppressor mount and provide extremely low POI shift Package Contents: Griffin Armament DUAL-LOK 2.25in Stealth Flash Hider Griffin Armament DL225FH5824: DUAL-LOK 2.25in Stealth Flash Hider 7.62x39mm 5/8x24 QPQ Nitride Black