Lang Yarns Twin Soxx 4-Ply is a yarn for knitting socks and sweaters composed of 75% virgin wool and 25% superwash nylon to strengthen the wool.
It knits with knitting needles 2.5 and 3.5 mm (US -4) for a gauge of 30 stitches and 41 rows for a 10 cm (4") swatch.
In a 100 gram ball there are about 420 meters (459 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.