This is a 3-inch by 100-yard roll of unbleached muslin (woven cotton) fabric used as a pulling strip during hair-removal waxing services. Muslin strips like this one are pressed onto soft/strip wax and pulled away to remove hair from the skin — the fabric's tight weave grips the wax so it lifts cleanly in one motion.
Because it comes as a continuous roll rather than pre-cut strips, estheticians and waxing technicians cut it to whatever length suits the area being treated, from small facial sections to full-leg or back passes. A cut strip can often be reused for a second pull on the same client before being discarded.
This roll is a bulk professional supply meant for salons and spas performing repeated waxing services, rather than a small single-use retail pack.