The 3M Littmann Classic II S.E. Teaching Stethoscope is an excellent choice to use to educate students. Its dual headsets for teacher and patient use makes it the ideal educational tool. It has a 40 inch tube to allow maneuverability around a patient. One side contains a traditional bell, while the other contains a pressure-based frequency adjustment that features a tunable diaphragm. This tunable diaphragm enables you to hear high and low frequency by applying or easing up on pressure. The 3M Littman Classic II S.E. Teaching Stethoscope rates a seven on a ten point scale to allow prime sound transfer. The headset features an anatomical design that helps it comfortable fit in your ears and makes it easy to use.