They come with a mounting nut and are available in 10-32, 1/4-28, 1/16, 1/8, 1/4, and 3/8 female heads. Standard bulkheads are white or black. Bulkheads made from other materials are also available as are color options in both bulkheads and corresponding mounting nuts.
Industrial Specialties Mfg. Inc., 2741 W. Oxford, Unit #6, Englewood, CO 80110, (303) 781-8486, industrialspec.com