It may not be very valuable, but it is very memorable to collect.

Modern darning has been widely used in clothing, shoes and hats, underwear, stockings, household bedding, scarves, luxury goods, works of art and other fields, involving woven fabrics, knitted fabrics, leather, various nonwovens, blankets and so on. Fine darning technology can be used for wool, cashmere and knitting, and imitation darning technology can be used for denim fabrics and cloth fabrics. There are many darning and imitation darning that can't be darned, such as embroidery darning, sewing, even painting darning and dipping darning.