True weight is Fingering, but works better when used with Sport gauge. Held double, it can work for Worsted patterns.
http://www.hilosomega.com.mx recommends 6 1/2 to 7 US knitting needles, or a size “(D/)2 US” crochet hook.
Crochet hook US E/F also suggested.
Compares to No. 5 crochet cotton.