CPAP has been proven to provide an effective method of treating respiratory distress from CHF. The use of CPAP is now being extended to other respiratory problems to provide symptom relief and avoid the need for intubation and ventilation of the patient and ICU admission. The o_twoTM Single-Use Open CPAP Delivery System provides incredibly accurate CPAP delivery for such a compact device. By minimizing the pressure drop on inspiration and the peak pressure on expiration, the o_twoTM Single-Use Open CPAP Delivery System produces a more uniform CPAP pressure throughout the respiratory cycle. This provides a lower work of breathing for the patient when compared to other, commonly used, pre-hospital devices.