37 Installation, repair and maintenance services, of pumps, sewage treatment machines, lavatories, toilets, toilets with sterilizing functions, toilets with washing functions, portable toilets, toilet cisterns, water flushing installations, filter elements for the air vents of water supply tanks; Installation, repair and maintenance services, of apparatuses and instruments for conducting, switching, transforming, accumulating, regulating or controlling electricity, apparatuses for controlling air conditioning installations, heating installations, toilets in vehicles and ships, installations for airing, aeration apparatuses, electrically powered blowers for ventilation, electric air conditioners, air conditioners for vehicles, air conditioners for ships, air conditioning filters, fans being parts for air conditioner installations, air conditioning fans, electric cool boxes, heat pumps, electric water heaters, air purifiers, demisters in the nature of in the nature of separators used to clean and purify vapor streams, defrosters for vehicles, and pervaporisers in the nature of separators used to clean and purify liquids