Amazon.com: Durabasics Classic 3, Cardiology 3 & Cardiology 4 Stethoscope Accessories Kit for Littman Stethoscope Replacement Parts & Littmann Stethoscope Parts - Fits Classic III, Cardiology III & IV - Black : Industrial & Scientific
LITTMAN Stethoscope Spare Parts Kit, Cardiology IV and CORE, Gray (3M40017) | Zoro