USED JMac Customs Folding Stock/Brace Mount for 5.5mm Folding AKs Black SM-5.5. 591'' gas block barrel journalsHas 90 gas port and is a direct replacement for most 90 gas blocks will work on 45 gas ports with minor gun-smithing. Uses standard front sight windage drum and pin. Available with detent and spring at 12 o'clock location (available for purchase here -Spring and Detent) (accepts standard AKM spring and detent)Has built in cleaning rod holderCast in the US using Wax Casting techniques similar to the modern Russian barrel components. Machined in the US4140 Heat Treated to Rockwell 32CBlack Nitrided in the USWe recommend having a Kalashnismith install these:It all started with a high definition scan of an original part from Larry Vickers then we teamed up with Sabrewerks13 to oversee the casting process and finally back to us for machining. PLEASE READ THIS FIRST: These come stripped they do not include the indage drum front sight post detent spring or barrel component pins. Specifications for JMac Customs Brace Mount for 4.5mm AKs Folding Stock: Manufacturer: JMac Customs Color: Black Gun Type: Rifle Fabric/Material: 7075 Aluminum Features of JMac Customs Brace Mount for 4.5mm AKs Folding Stock Adjustable Gas block to replace or upgrade 90 Gas Blocks perfect for 14.5'' pin/weld or SBR/Pistol Front Sight Post Spring and Detent 24mm Threads Package Contents: JMac Customs Brace Mount for 4.5mm AKs Folding Stock JMac Customs SM-5.5: Folding Stock/Brace Mount for 5.5mm Folding AKs Black