TRULOCK Fleecy Nylon is a soft, textured nylon thread for your serger that performs perfectly with elastic fabrics like lycra or jersey knit, and that also gives great coverage for seams and rolled hems. It's soft enough for uses in apparel - both lingerie and baby - next to your skin and strong enough to perform in today's high speed home sergers. Use in the upper or the lower looper of the serger. A size 90/14 needle is recommended for this thread.