 Common binding materials include cloth strips, elastic or non-elastic bandages, purpose-built undergarments (often using spandex or other synthetic fibre) and shirts layered from tight to loose.The act of breast binding is common for trans men, but is also done by androgynous and non-binary people, as well as crossdressers, cosplayers, and performers.In a general sense, women may also use binders as alternatives to bras or as a practice of propriety.