Basic Definition

Refers to the number of weft threads per warp threads. Most denims are a 3x1 weave, though some light weight denim can be a 2x1 weave. When woven a 3x1 weave runs: over, over, over, under, over, over, over, under, over, over, over, etc. For comparison, a 1X1 weave would run: over, under, over, under, over, under etc.
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