What are Super 100s, 110s, 120s, 130s, 150s, and 180s?
It represents the fineness of fabric yarn. The higher the number the greater the fineness. The yarn number for cotton is based on the number of 840-yard hanks in a pound. The convention for indicating plies resembles that for wool. Two-ply 20s would be written 2/20s or 20/2, and would be twice the weight, length for length, of single ply 20s yarn.
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