Visual – accoustic signaller type.ESOA-1.1.1.2.0.0 is designed to emit signals of acoustic and optical warning emission, and can be used in non-hazardous areas, in methane fields of mining companies, in the premises belonging to the a, b or c degree for explosion, gas environment belonging to the group I of explosion or in explosive coal dust areas. Meets the requirements for devices of group I category M1.