1.1 This practice covers instructions for the designation of yarn construction and is applicable to single yarns, plied yarns, and cabled yarns or cords of filaments or spun fibers. The application of the practice to specific cases is illustrated with examples. This practice does not cover the description of novelty yarns or core spun yarns of various types.

1.2 The primary purpose of this practice is to establish a reference system for use in the trade and particularly for use in correspondence and publications. To secure a simplified notation, certain portions may be omitted provided there is no doubt as to the omitted parts.