Question: what is the difference between blue and green acapella?
Answer: Acapella Blue – produces a lower amplitude of vibrations compared to Acapella Green or Acapella Choice. Acapella blue is generally used for individuals with a flow rate of < 15L/min. ... Acapella Green – used for flow rates of > 15L/min. Acapella Choice – used for flow rates of > 15L/min.