Lang Yarns Suri Alpaca, color 0019, is a soft yarn composed of 100% Suri alpaca and knits with knitting needles 4.5-5 mm for a gauge of 16 stitches and 24 rows in a 10 cm (4") swatch.
In a 25 gram ball there are about 100 meters (109 yd) so to knit a long-sleeved sweater allow:
500 g = 20 balls for men size M
350 g = 14 balls for women size M
250 g = 10 balls for children 10 yrs.
Hand wash with detergent for wool without softener.