Fast, accurate lung function monitor for use at home, in primary or secondary care. Provides accurate and effective monitoring of lung function for respiratory conditions, including COPD, cystic fibrosis and for post-transplant patients. Measures FEV1, FEV6 and calculates the ratio. Large, easy-to-read display. Displays % of personal best FEV1. Electronic record - no need for record cards. Automatically stores best values in a test session. Quality-of-blow indicator. 200-test memory. Suitable for multi-subject use in clinic with Bacterial Viral Filters (BVF).