What it is
Metric count Nm: tex = 1000 / Nm. Larger is finer. Not nanometres, not needle NM.
How to use
Nm = 1000 ÷ tex. 25 tex = 40 Nm. Inverse conversion above.
Nm = 1000 ÷ tex
Example: 1 tex = 1000 Nm
Common uses
Worsted, wool, some sewing threads.
Conversion tips
Inversely proportional to tex. Not a needle size.