JMac Customs 4C 1/2-28 4-Port Face Muzzle Brake with KeyMount Black Nitride Black. These Muzzle Devices designed by JMac Customs are constructed from rugged 17-4PH stainless steel and are nitride finished to resist wear and corrosion over time. This JMac Customs 4C Muzzle Brake KeyMount Attachment adds just 1.5" to your barrel and the sleeve inside the device will swell up to 1.32" to accommodate a suppressor - preventing the device from being overly restrictive. Stop damaging your firearm and pick up a JMac Customs 4C 1/2-28 4-Port Face Muzzle Device KeyMount to outfit your firearm with a highly precise recoil reduction system. Specifications for JMac Customs 4C 1/2-28 4-Port Face Muzzle Brake w/ KeyMount: Manufacturer: JMac Customs Color: Black Finish: Nitride Fabric/Material: 17-4PH Stainless Steel Threads per Inch: 1/2x28 Gun Make: Kalashnikov Length: 2.82 in Weight: 3.6 oz Condition: New Features of JMac Customs 4C 1/2-28 4-Port Face Muzzle Brake w/ KeyMount 4 Port Muzzle Brake with KeyMount Package Contents: JMac Customs 4C 1/2-28 4-Port Face Muzzle Brake w/ KeyMount JMac Customs RRD-4C-28F-KM: 4C 1/2-28 4-Port Face Muzzle Brake with KeyMount Black Nitride Black