Lang Yarns Merino 50 knitting yarn is a heavy weight yarn composed of 98% merino wool and 2% polyester and knits on knitting needles 9 mm (US 13 / UK 00) for a gauge of 12 stitches and 19 rows.
There are about 90 meters (98 yds) in a 100 gram (3.50 oz) ball so plan on:
950 g = 10 balls for Men size M
800 g = 8 balls for Women size M
600 g = 6 balls for Children 10 yrs.
Machine washable at 30°C (86°F) with detergent for wool without softener, iron at low temperature.