electrical and optical apparatus and instruments for weighing, measuring, signalling and supervisory checking; namely, data processors, benzine meters, petrol level gauges, self regulating petrol pumps, self-regulating fuel pumps and petrol pumps for service stations; safety and functionality alarms for the petrol and petrochemical industries; detectors for liquids, gases, objects and persons for use in the petrol and petrochemical industries; dosage dispensers and dosimeters; electric coupli...