The next generation in electronic stethoscopy combining impressive acoustic amplification, electronic noise filtering, and comfortable ergonomic design. Amplifies up to 16x (24db) over traditional acoustic scopes. Patented piezoploymer film contact microphone provides wider frequency response than acoustic mikes used in competing models. Three frequency modes: Bell (15-200Hz) for cardiac sounds, Diaphragm: 100-500Hz for lung sounds, Extended Range: 15-1000Hz allows the practitioner widest frequency response). 8 level volume control. Holds last mode and volume setting foe convenience. Auto-shut off after 3 minutes extends battery life. Battery warning LED signals when replacement is needed. Binaurals fixed at 15° angle for snug anural fit. Specially constructed Adsoft™ PVC eartips for the ultimate in wearing comfort and acoustic seal. Lightweight and compact-weighs under 6oz., measures just 28". Uses AAA Lithium battery (included). Two year warranty. Made in Korea, Inspected in U.S.A.