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: M16x1 LH. Made from 7075 hardened AL. Fits the following platforms*: H&K USP Tactical .45