Mule Emergency Lighting, Inc. was founded in 1923, originally as a battery manufacturer of automotive and truck batteries for long forgotton autos like the Cord, Durant, Essex, Pierce-Arrow, Desoto and Marmon.. Today Mule enjoys an envied reputation as a quality manufacturer of quality lighting and battery related products. Such product lines as Exit Signs, Emergency Lighting, Battery UPS systems, Battery Chargers and Rechargeable Batteries are Mule's central product offerings, but our research continually brings us into new product areas as these industries evolve.