Needle Plate Screws Compatible with Singer Brand Industrial Sewing Machines. Part Number # : 691 Compatible with Singer models : 6-11, 6-12, 6-14, 6-15, 17-1, 17-2, 17-3, 17-4, 17-5, 17-6, 17-7, 17-8, 17-9, 17-10, 17-11, 17-12, 17-13, 17-14, 17-15, 17-16, 17-18, 17-19, 17-20, 17-21, 17-22, 17-23, 17-24, 17-25, 17-26, 17-27, 17-28, 17-29, 17-30, 18-1, 18-2, 18-3, 18-5, 18-6, 18-14, 18-15, 18-16, 18-17, 18-18, 18-23, 18-25, 24-56, 25-54, 25-55, 31-51, 31-52, 31-53, 31-54, 31-60, 31-61, 31-63, 31-64, 31K19, 31K21, 31K47, 37-2, 37-3, 37-4, 37-5, 37-6, 37-7, 37-8, 37-9, 37-10, 41-3, 41-4, 41-5, 41-6, 41-7, 41-8, 41-9, Centurion 121D You will receive 6 screws.