 In addition, one or two smaller “fine” pitches are defined, for use in applications where the height of the normal “coarse” pitch would be unsuitable (e.g., threads in thin-walled pipes).The terms “coarse” and “fine” have (in this context) no relation to the manufacturing quality of the thread.In addition to coarse and fine threads, there is another division of extra fine, or “superfine” threads, with a very fine pitch thread.