3M Littmann Classic II S.E. Teaching Stethoscope, Black and Burgundy Tube, 40 inch, 2138 High acoustic sensitivity in a dual-sided chestpiece combines with durable, compact design to deliver versatile auscultation and rugged dependability Tunable diaphragm responds with a simple pressure change to capture low and high-frequency sounds without the need to turn over the chestpiece Anatomically designed headset is angled to meet the path of the ear canal and provide optimal listening Latex-free materials for allergy sensitive users Non-chill rim and diaphragm provide welcome patient comfort