ADC Proscope stethoscopes combine lightweight comfort, sensitive acoustics, and handsome styling, with truly affordable pricing. The Proscope Series features a choice of diaphragm only (660 series) or combination (670 series) chestpiece. Lightweight aluminum chestpiece construction. Non-chill diaphragm rim for patient comfort. Proprietary diaphragm enhances acoustic response by 50% over traditional designs. Adjustable chrome-plated brass binaurals with PVC eartips. Flexible 22" PVC tubing. Spare pair of black mushroom eartips included. Inspected and packaged in the U.S.A.. Choice of 21 tubing colors. One Year Warranty Combination diaphragm/bell chestpiece for wide frequency response. Diaphragm diameter 13/4", bell diameter 3/4". Non-chill bell ring and diaphragm for patient comfort. Weighs 3.5 oz. Overall length 32.5".