Lungtest 250 and Lungtest 250 Compact spirometers are small portable electronic devices designed for basic spirometric tests. Spirometers contains a built-in specialized computer for performing tests and developing results, and an accurate measurement system based on precise semi-conductor sensor. The units are equipped with patented replaceable pneumotach headpieces protecting patients against infection. Basic advantages: automatic control of performed tests according to ERS recommendations, monitored in real time with a counter of correctly performed flow-volume loops information on meeting ERS recommendations printed together with test results sound signal if time is exceeded by 3 seconds upon recording of forced exhalation possibility of 5-hour operation without additional battery charging (LUNGTEST 250) power supply and built-in thermal printer (LUNGTEST 250 Compact) easily readable LCD for observation of diagrams and tables of results modern pneumotach headpieces immediately ready-to-use after replacing a headpiece comparison of tests performed before and after medicine intake comparison of the results with predicted values database for 30 tests data transmission into PC small size and low weight