Mary Johnston Letellier
Deep Breathing Exerciser
This is the Deep Breathing Exerciser. It costs $18 and is available on Amazon.
The goal is to have a powerful enough inhalation to cause all the colored balls to rise to the top. This exercise can help to increase lung expansion, which can be especially beneficial to singers that suffer from asthma or are recovering from a prolonged illness.
I do not find the tool useful in increasing exhalation function, however, and must therefore recommend the Flow-Ball as the better breath support tool for singers.