Lace or cotton triangle bras and bralettes to wear under a deep-cut tank top: soft models without underwire or padding, designed for lightness rather than support.
A triangle bra is made up of two triangles of fabric without underwire or constructed cups; a bralette follows this principle but adds a wider back band and often decorative lace designed to be seen. The non-wired triangle bra is by far the most common, but there are now versions with fine underwires for those seeking a bit more support. Neither aims for major hold: they cover, adorn, and are easy to forget.
Petite to medium busts, up to about a C cup, will find a comfortable and pretty piece that doesn’t compress. Beyond that, fabric alone can’t support the volume: the bralette distorts and the straps dig in. The structured triangle bra, known as a padded bralette, with reinforced cups and a wide elastic back band, pushes this limit a bit, but a larger bust is better served by a full-cup style without underwire.
That’s actually its purpose today. Under a deep-neck tank top, a blazer worn alone, or an open shirt, the lace that peeks out is part of the outfit. The buying criteria then change: one considers the lace design, the strap finish, and the cleanliness of the back as much as comfort. Styles with decorative backs, cross-over or racerback designs, are made to be seen under a swimmer's back.
Most of these styles are sold in sizes S, M, L, which simplifies things but makes fitting less precise. If you are between two sizes, go for the smaller one: these pieces stretch with wear, and a bralette that's too big won't hold anything. Styles offered in classic numbered sizes, which are rarer, are preferable once you go beyond a B cup.