This massive set features tools perfectly crafted for hand-threading a variety of materials. Fractional: 1/4″ – 20 NC, 1/4″ – 28 NF, 5/16″ – 18 NC, 5/16″ – 24 NF, 3/8″ – 16 NC, 3/8″ – 24 NF, 7/16″ – 14 NC, 7/16″ – 20 NF, 1/2″ – 13 NC and 1/2″ 20 NF.