Electronic air leak testers that utilize air pressure for detecting defects including pinholes and cracks of fuel tanks of vehicles, fuel injectors of vehicles, motors of vehicles, batteries of vehicles, mufflers of vehicles, evaporators of air-conditioners, compressors of air-conditioners, gas combustion appliances, gas meters, water meters, pumps, pipes, electronic parts, medical instruments, food packaging, containers, cylinders, valves, pressure sensors, cameras, cell phones and watches; Electronic leak testers that utilize hydrogen gas for detecting defects including pinholes and cracks in fuel tanks of vehicles, fuel injectors of vehicles, motors of vehicles, batteries of vehicles, mufflers of vehicles, evaporators of air-conditioners, compressors of air-conditioners, gas combustion appliances, gas meters, water meters, pumps, pipes, electronic parts, medical instruments, food packaging, containers, cylinders, valves, pressure sensors, cameras, cell phones and watches; Electronic leak testers that utilize helium gas for detecting defects including pinholes and cracks in fuel tanks of vehicles, fuel injectors of vehicles, motors of vehicles, batteries of vehicles, mufflers of vehicles, evaporators of air-conditioners, compressors of air-conditioners, gas combustion appliances, gas meters, water meters, pumps, pipes, electronic parts, medical instruments, food packaging, containers, cylinders, valves, pressure sensors, cameras, cell phones and watches; Electronic leak testers that utilize information on flow rate of compressed air for detecting defects including pinholes and cracks in fuel tanks of vehicles, fuel injectors of vehicles, motors of vehicles, batteries of vehicles, mufflers of vehicles, evaporators of air-conditioners, compressors of air-conditioners, gas combustion appliances, gas meters, water meters, pumps, pipes, electronic parts, medical instruments, food packaging, containers, cylinders, valves, pressure sensors, cameras, cell phones and watches; Electronic leak testers for detecting defects including pinholes and cracks of fuel tanks of vehicles, fuel injectors of vehicles, motors of vehicles, batteries of vehicles, mufflers of vehicles, evaporators of air-conditioners, compressors of air-conditioners, gas combustion appliances, gas meters, water meters, pumps, pipes, electronic parts, medical instruments, food packaging, containers, cylinders, valves, pressure sensors, cameras, cell phones and watches; Pressure gauges; Pressure sensors; Differential pressure sensors; Air flow gauges; Gas flow gauges; Flow sensors; Digital pressure indicators; Pressure indicators; Flow indicators in the nature of flow meters; Leak amount indicators for use with electronic leak testers for detecting defects including pinholes and cracks of fuel tanks in vehicles, fuel injectors of vehicles, motors of vehicles, batteries of vehicles, mufflers of vehicles, evaporators of air-conditioners, compressors of air-conditioners, gas combustion appliances, gas meters, water meters, pumps, pipes, electronic parts, medical instruments, food packaging, containers, cylinders, valves, pressure sensors, cameras, cell phones and watches; Electronic leak detection hardware in the nature of mock leak generators; [ Nozzle diameter measuring instruments using air pressure sensors; Pressure-resistance test machines using liquid pressure sensors; ] Pressure regulators, pressure controllers and flow regulators designed for use with electronic leak testers for detecting defects including pinholes and cracks in fuel tanks of vehicles, fuel injectors of vehicles, motors of vehicles, batteries of vehicles, mufflers of vehicles, evaporators of air-conditioners, compressors of air-conditioners, gas combustion appliances, gas meters, water meters, pumps, pipes, electronic parts, medical instruments, food packaging, containers, cylinders, valves, pressure sensors, cameras, cell phones and watches