Fitting has three outer thread dimensions, ¾ NPT, 13/16-16 and ¾-16UNF.Accepts JÄGER Re-Direct Flash Hiders, JÄGER "Versa-Brake" System, Gestalt Verdampfen Compensator and Ferragane Mini..  Inner dimension of 14mm x 1 LH.  Made from hardened carbon steel with Anti-Rust Black Oxide matte finish.  Fits the following platforms*: 7.62X39 AK47 and similarly threaded AK clones and derivatives.   * To ensure proper fit, confirm your rifle's thread dimensions prior to purchase of this part.