Worsted Weight Yarns

Worsted weight yarns 
18-20 stitches per 10cm/4 inches
with 4.5mm-5mm / US7-6
9 wpi
10 ply
Yarn Standard #4
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There is some variation between yarns within the same yarn weight category. To find the right yarn to suit your project: look up the recommended yarn for your pattern and compare that yarn's gauge to the gauge of the yarn you would like to use.