The conk (derived from congolene, a hair straightener gel made from lye) was a hairstyle popular among African-American men from the 1920s to the 1960s. This hairstyle called for a man with naturally "kinky" hair to have it chemically straightened using a relaxer (sometimes the pure corrosive chemical lye), so that the newly straightened hair could be styled in specific ways. Often, the relaxer was made at home, by mixing lye, eggs, and potatoes, the applier having to wear gloves and the receiver's head having to be rinsed thoroughly after application to avoid chemical burns. Conks were often styled as large pompadours although other men chose to simply slick their straightened hair back, allowing it to lie flat on their heads. Regardless of the styling, conks required a considerable amount of effort to maintain: a man often had to wear a do-rag of some sort at home, to prevent sweat or other agents from causing his hair to revert to its natural state prematurely. Also, the style required repeated application of relaxers; as new hair grew in, it too had to be chemically straightened.