What does 3×1 Weave mean?

Referring to the number of weft threads per warp thread, in which three threads cross every one (hence, 3×1 weave)

Heddels explains 3×1 Weave

Denims that have heavier weights (over 10.5 Oz / square yard) are 3×1 weaves, especially compared to denim with a 2×1 weave (under 10.5 Oz / square yard).

Additional Resources

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