Marr Fan 1. external rotor fan with a compact, easy to install, reliable operation, low noise, energy efficient features. 2. Our products are widely used in hotels, restaurants, industrial and mining enterprises, office buildings, theaters and other buildings and facilities, as a cold storage freezer equipment or ventilation purposes, (eg supermarket freezer refrigerator, ice maker, air coolers, chillers, condensing refrigeration units and other equipment or facilities, and dehumidifiers, evaporator, sidewall fans, fire fans, central air conditioning fans and other equipment for use.