3M Littmann Cardiology III Stethoscope, Brass-Finish Chestpiece, Black Tube, 27 inch, 3128BRS The only dual-sided chestpiece in the Cardiology line provides versatile auscultation for both adult and pediatric patients Two tunable diaphragms respond with a simple pressure change to capture low and high-frequency sounds Expand versatility by converting pediatric side to open bell for low frequencies, using the nonchill bell sleeve (included) Two-in-one tube design (dual lumen) eliminates noise interference from two external tubes rubbing together Anatomically designed headset is angled to meet the path of the ear canal