These top-quality firing pins are .075 in diameter, precision turned from heat-treated tool steel and are the proper weight for positive ignition with heavy duty springs and any type primer. Minor fitting may be required.NotesAverage diameter of 1911 .45 caliber firing pins is .095"-.096" at tip. The average diameter of 1911 .38 Super and 9mm caliber firing pins is .070"-.071" at tip. If the firing pin caliber needed is not known, check the hole size in the recoil face to determine the caliber firing pin needed for your slide before ordering.For use in Springfield made 1911 type pistols in 38 and 9mm.