Gas Block Combo 13 Collab with Sabrewerks13 With detent hole This HAS a detent hole in the front GBC-13 is a copy of the East German 74nk Front Sight Gas Block Combo Perfect for Pistol, SBR, and Rifle builds to lighten up the front end and give it a custom look Fits common 0.591"" gas block barrel journals Has 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 for purchase here - Windage Drum Front Sight Post Available with detent and spring at 12 o'clock location. Accepts standard AKM spri Mfg: Jmac Customs