Peak flow meters measure the air pushed out of your lungs. **Key Benefits:** - Measures PEF from 30-400l/min - Suitable for children and patients with severe respiratory conditions - Easy to read scales, compact and lightweight - Calibrated by hand to ensure 100% accuracy - AFS technology ensures readings comparable with those from Standard Range Mini-Wright Peak flow meters come in two ranges to measure the air pushed out of your lungs. A low-range peak flow meter is for small children, and a standard-range peak flow meter is for older children, teenagers and adults. An adult has much larger airways than a child and needs the larger range. The AFS Low Range Peak Flow Meter offers help to patients who cannot obtain a high PEF reading. It is suitable for children and those with severe respiratory problems.