JMac Customs GFHC 1/2-28 KeyMount KeyMicro Black. In order to use this device with a suppressor it must be installed by a professional - to ensure it is properly mounted and aligned. Do NOT shoot without checking alignment with bore rods. JMac Customs is not responsible for any damage to the suppressor or any injury resulting from improper installation. Some firearms are NOT suitable suppressor hosts just because you can thread this muzzle device on does NOT mean it is safe to use. The GFHC is a combination of the German G36 flash hider and DeadAir Silencers KeyMount. THis is the compensator version that has to be timed in order to reduce muzzle rise. SHIMS ONLY NEEDED FOR TIMING. Specifications for JMac Customs GFHC 1/2-28 KeyMount - KeyMicro: Manufacturer: JMac Customs Color: Black Finish: Nitride Fabric/Material: 17-4PH Stainless Steel Threads per Inch: 1/2x28 Gun Make: Kalashnikov Length: 2.7 in Weight: 4.5 oz Features of JMac Customs GFHC 1/2-28 KeyMount - KeyMicro G36 Style Flash Hider Comp with KeyMount Feature Package Contents: JMac Customs GFHC 1/2-28 KeyMount - KeyMicro JMac Customs GFHC-28S-KM: GFHC 1/2-28 KeyMount KeyMicro Black