Tinsel Wire

Tinsel wire is a form of low voltage electrical wire used when maximum mechanical flexibility is required. It is commonly found in cords used for telephones, especially the handset cords, and in headphones. Because of its extreme flexibility it is much more resistant to failing as a result of metal fatigue than ordinary stranded wire or solid wire. Tinsel wire is also used in the power cable for very small appliances such as electric shavers or clocks, where stranded cable conductors of adequate mechanical size would be too stiff. "Tinsel cords" are recognized as type TPT or TST in the US and Canadian electrical codes, and are rated at 0.5 amperes.

Tinsel wire is made by wrapping several strands of thin copper foil around a textile core. Because the foil is very thin, it is extremely flexible; the extreme thinness of the foil means that the minimum bend radius imposed on the foil is many times the thickness of the foil, leading to a low probability of metal fatigue. Meanwhile, the fabric core provides high tensile strength.

Separated from the core, the individual foils are relatively fragile, and the textile core can be damaged by high temperatures. Together, these two factors make it difficult or impractical to terminate tinsel wire by soldering during equipment manufacture, although soldering is possible, with some difficulty, to repair a failed connection. Although soldering may be used for emergency repairs, the foil conductors tend to break at their junction with the rigid solder. Instead, crimped connections are commonly used. Usually the connector has a series of barbs that pierce the insulation of the tinsel wire, allowing the connection to be made without the need to strip the insulation off the conductor.