5 Weight Yarn
CYC 5 weight is also called Bulky, Chunky, Craft, and Rug. This weight of yarn is made for large hooks and needles and is ideal for outer garments such as Sweaters and Scarves. Some even use this yarn weight to make rugs and throws. Crochet hook sizes 6.5 mm to 9 mm or K-11, L, M and N. Knitting needle sizes 5.5 mm to 8 mm or sizes 9, 10, 10.5 and 11.
Source: Craft Yarn Council of America's www.YarnStandards.com