The MARK 7A Respirator combines the reliability and simplicity of the Mark 7 Respirator with unique pneumatic technology designed to improve the effectiveness of IPPB therapy. The MARK 7A Respirator features Apneustic Flowtime, a mechanical means of simulating a dynamic (time-cycled) post- inspiratory breath hold for increased distribution and retention of inspired aerosols. During the time cycled breath hold phase a low flow of gas is delivered through the nebulizer, creating a very dense aerosol for delivery to the airway. The duration of the breath hold is controlled by the operator. The Apneustic Flowtime feature is further complimented by the independent flowrate control which permits precise regulation of the gas flowrate, giving the clinician control of one of the most important variables in effective and safe IPPB therapy. Does not come with stand.