This is 100 mouthpieces. The low-cost alternative to Midmark Spiro Mouthpieces! It just makes sense. SDI's easy-to-use mouthpieces are ideal for both adult and pediatric patients. Why pay more when we provide the same quality and performance as other manufacturer's specifications at a fraction of the cost. Meets or exceeds all American Thoracic Society specifications, and is substantially equivalent to the MidMark IQ Mouthpiece™. These mouthpieces are available in quantities of 100 or 300.