Welch Allyn/Hillrom Spirometer Flow TubesWelch Allyn Hillrom Spirometer Flow Tubes Spirometer flow tubes (or flow transducers) are components used in spirometry to measure airflow during breathing tests (inhalation exhalation). They detect the pressure or flow through the tube when a patient breathes into the spirometer. These often come with or without other parts (tubing, handles, sensors etc.). Some are disposable, some are reusable depending on design. SKU Product Description Product Key