Can you get a prescription for AirPhysio?

Could you please clarify if it's possible to obtain a prescription for AirPhysio? I understand that AirPhysio is a device marketed for respiratory health, but I'm unsure if it requires a doctor's recommendation or if it's available over-the-counter. If a prescription is needed, what specific medical conditions would typically warrant its use? Additionally, what steps should one take to ensure they're using AirPhysio safely and effectively?