SDI Diagnostics

SDI Diagnostics is a private U.S. medical device company focused on respiratory diagnostic tools and consumables, especially spirometry and pulmonary function testing products. Founded in 1978, the company supplies FDA-approved spirometers, pulmonary filters, flow sensors, mouthpieces, nose clips, software, and related accessories for healthcare professionals and distributors. Its branded spirometry lineup includes products such as the Astra BT, Astra300, and AstraTouch spirometers, alongside compatible consumables for systems from other respiratory device brands. The business appears to operate as a commercial-stage manufacturer and distributor serving clinics and respiratory care settings across the United States.