An acrochordon (plural acrochorda; also known as a skin tag or fibroepithelial polyp) is a small benign tumor that forms primarily in areas where the skin forms creases, such as the neck, armpit, and groin. They may also occur on the face, usually on the eyelids. Acrochorda are harmless, are typically painless and usually do not grow or change over time. Though tags up to a half-inch long have been seen, they are typically the size of a grain of rice. The surface of an acrochordon may be smooth or irregular in appearance and is often raised from the surface of the skin on a fleshy stalk called a peduncle. Microscopically, an acrochordon consists of a fibro-vascular core, sometimes also with fat cells, covered by an unremarkable epidermis. However, tags may become irritated by shaving, clothing, jewellery or eczema.