Model S700. A horizontal, dry, rolling-seal volume displacement spirometer. Manufactured by Graseby-Andersen which marketed it under the brand name Spirotech. From http://www.sensagent.com/ebay/search-item.jsp?iId=350801506121&sId=-1&dl=en
Model S700. A horizontal, dry, rolling-seal volume displacement spirometer. Manufactured by Graseby-Andersen which marketed it under the brand name Spirotech. From http://www.sensagent.com/ebay/search-item.jsp?iId=350801506121&sId=-1&dl=en