Disposable Bacterial Filter, disposable microbacterial filter significantly reduces need to sterilize your spirometers flow head, 30 mm ID opening allows for an easy, air-tight fit to the flow head
EKG Ruler, features are Seconds scale for PR, QRS, Cycle, Length, Coupling, Escape, and Parasystolic Intervals, Offers both 1 and 2 cycle scales, small enough to fit in a medical coat pocket, Complete with protective sleeve, Size: 1 11/16 x 6 3/8 in