The term "gel bra" is most often used to describe a bra with fluid-filled or gel inserts designed to enhance the bust line. Such bras are most often used to provide lift and to create more dramatic cleavage. They come in a variety of sizes, colors and styles and are available through a number of manufacturers. Gel bras can be purchased from online specialty companies, in most lingerie boutiques and in the lingerie department of many department stores and women's clothing stores.
A gel bra is manufactured by creating shaped inserts, usually made of flexible plastic or PVC, filling them with gel, and placing them into pockets sewn into the inner surface of the bra cup. Many bras of this type are designed to be worn with or without the inserts, depending on the look the wearer wishes to achieve. Gel inserts are most commonly found in bras already designed to create lift, such as structured-cup bras and underwire bras. They are also seen frequently in bras that are designed for evening wear, such as strapless, low-back and plunge bras.
The inserts are most commonly placed in the bottom half of the cup to create lift. They may also be angled so as to push the breasts in, enhancing cleavage. Some manufacturers offer inserts that can increase the apparent size of the breasts by a cup size or more.
Most gel bras use silicone gel, though a few use other materials. A bra with air pillow or water-filled inserts may give results that are similar to a gel bra. Usually, the heat of the body warms the gel, allowing the inserts to mold around the wearer's breast, offering a more natural look. Some gel inserts, however, are designed to be chilled or frozen, increasing the appearance of "perkiness."
Gel bras can be worn with almost any outfit, but are most often chosen as the foundation for outfits that emphasize the bust. Dramatic cleavage can be created by pairing a gel bra with a dress or blouse with a low neckline or a plunging v-neck. Gel inserts should always be removed before machine-washing.
Some bikinis and bathing suits contain built-in gel bras as well. Gel inserts may also be purchased separately and used with the wearer's existing bras. Such inserts, or pockets for such inserts, may also be found in formal dresses that have necklines or other design features that do not allow for a bra.