Riot-control spray, commonly referred to as MACE, is a chemical agent used to control and disperse crowds. It is typically used by law enforcement officers in situations where crowd control is necessary. MACE is an aerosol spray that contains a mixture of chemicals, such as pepper spray, tear gas, and other irritants, which can cause temporary blindness, coughing, and difficulty breathing. It is designed to be non-lethal and is often used in conjunction with other forms of crowd control, such as batons and shields.