The Triflo II Inspiratory Exerciser, by Teleflex Medical, is a training device to strengthen breathing muscles. You push air through a mouthpiece connected to a unit with three chambers, each containing a color-coded ball with the minimum flow imprinted on the outside of each chamber. As you take deep breaths to push air into the exerciser, it lifts the color-coded balls with an airflow rate of 600 to 1200 cc per second. When all three balls reach the top it means that you have reached 1200 cc. The colored balls provide a visual indication of how your breathing muscles are working to incentivize progress through slow sustained maximal inspiration.
Its compact design makes it easy to hold and is preferably done when you are at rest, either lying down or sitting up. The durable break-resistant plastic holds up well and is latex-free.