69116 Volumetric Spirometer Coach 2 (Specifications One Way Valve To Ensure Patients Inhale Then Exhale, Adjustable Incentive Marker, Highly Visible Piston With Graphic, Oxygen Port To Allow Administration Of Supplement Oxygen, Scale With Smiley To Help In Visually Monitoring That Breathing Is Carried Out Correctly, Bed Rail Hook For Positioning At Bedside.