Wrist Strap Elastic Blue Antistatic 1.8m

Available in various other sizes and shapes, see here

ESD wrist straps also known as Antistatic wrist straps are used to prevent electrostatic discharge (ESD) by safely grounding a person working with electronic equipments or at an electronic assembly facility. It consists of a band of fabric with fine conductive fibers woven into it. The fibers are usually made of carbon or carbon-filled rubber and the strap is bound with a stainless steel clasp or plate. They are usually used in conjunction with an antistatic mat on the workbench or special static-dissipating plastic laminate on the workbench surface.