The yarn thickness is 60/2. bleach-proof Approximately 40 grams. Rare machine Embroidery Thread made in Switzerland. It was originally produce for big embroidery machines, this floss is suitable for your home embroidery machine, professional embroidery machine and hand embroidery. This yarn was originally bought in kilo grams by the embroiders and doesn't say how many meters a full spool of thread contains. It is thinner then the normal machine embroidery thread of Mettler, DMC or Güterman, which are 50 (at least the ones I have around). A Mettler cotton sewing spool weighs approx. 10 grams and contains 150m/164yds thread and a DMC machine embroidery thread with approx. 500m is about 20 grams. As the thread I am selling is thinner I am guessing you buy a couple 100m or yds which each spool