Lang Yarns Super Soxx Silk Color 4-Ply is a yarn for knitting socks and sweaters composed of 55% virgin wool, 25% superwash and 20% silk.
It knits with knitting needles 2.5 and 3.5 mm for a gauge of 30 stitches and 41 rows for a 10 cm (4") swatch.
In a 100 gram ball there are about 400 meters (437 yd) so to knit a long-sleeved sweater for women size M (38 / 40) you need about 5 balls (5 balls for men size M, 3 balls for children 10 yrs, 1 ball for socks).
Machine wash on a wool cycle up to 40°C (104°F) with detergent for wool without softener.