It glows! This may look like ordinary white yarn, but don't be fooled! When the lights go down, diy glow yarn turns up! This polyester yarn in a classic worsted weight is perfect for fiber artists of all skills and ages. Make glow-in-the-dark hats, scarves, and cowls for nighttime adventures, or add fun trims to costumes. Weight category: 4. Content: 100% polyester. Putup: 1.75oz/50g/ 74yd/65m. Gauge: 18sx24r = 4in/10cm on size us8/5mm knitting needles. Suggested crochet hook size: i-9/5.5mm. Dyelotted: we try but are not always able to match dyelots. Care: machine wash, machine dry, do not bleach, do not iron, do not dry clean.