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
Doppler Effect Demonstration Apparatus, 92dB buzzer, 0.8m tether. Nylon cord is 2ft 8in attached to a rugged ABS handle 8.5in long, (1in diameter), Swing the apparatus and students will be able to hear the change in frequency, Dimensions: 4.5 x 5 x 3 in