From official page:

This fine, silken yarn is created from 100% fine filament made from the raw silk of domesticated silkworms. It is repeatedly hand woven for optimal thickness. The luster and scroop of unprocessed, raw silk is incomparable. Use this yarn to create something to wear on a special occasion or make something treasured. This medium-fine yarn is also suitable for a crochet needle.

Stick Needle JP 2〜4
Crochet Needle JP 3/0〜5/0
Gauge 26-27 sts 28-29 rows

Average usage

• Women’s pullover: 350g
• Men’s pullover: 425g