Underwire - Underwire Construction

Underwire Construction

Underwire bras are built with a semi-circular "underwire", "bra wire", or "wire" embedded in the wire channel that circles the bottom and sides of each cup. One end, or head element, of the underwire is close to the front and center of the bra, and the other close to the armhole. The underwire can be made of metal or molded plastic; most are metallic. Plastic underwire has a very small share of the market because it does not provide the same support and rigidity offered by metal underwire. A metallic underwire is a thin strip of metal, usually with a nylon coating at both ends. Metals used include steel and nickel titanium, a shape memory alloy. According to underwire manufacturer S & S Industries of New York, which supplies underwire for bra makers such as Bali, Playtex, Vanity Fair, Victoria's Secret, Warner's, and other bra labels, about 70 percent of women who wear bras wear steel underwire bras.

When the underwire breaks through the bra fabric, it can cause tremendous discomfort. Celebrity chef, television personality, and businesswoman Clarissa Dickson Wright only wears a bra on special occasions. At her 50th birthday party, she was dancing when she suddenly felt a "terrifying pain in my chest." She initially thought she was having a heart attack. "The pain got more and more intense. I staggered off and discovered I'd broken my underwired bra."

Because underwire can tear through cloth, most women hand-wash underwire bras or machine-wash them on a delicate cycle. Bra wash bags, usually zippered mesh pouches, can also be used to protect bras and prevent the underwire from separating from the bra during machine washing.