The combination of the patented ERKA. dual-membrane and optimal sound chamber geometry enables optimal auscultation of both low and high tones, even in hard to reach auscultation points. The ERKA. Sensitive is the NonPlus-Ultra for a broad spectrum of possible applications in diagnostic medicine for the examination of heart, lung and bowel sounds. USER GROUPS: Anesthesiologists, cardiologists, emergency physicians, paramedics, family physicians, internists, assistant physicians, medical students, nurse anesthetists/caregivers, specialists in respiratory diseases 1_ The construction of the patented ERKA. dual-membrane allows for an additional resonance chamber which optimizes the sound. 2_ The non-chill ring ensures patient comfort and protects the membrane. 3_ Highly polished and chromium-plated for a non-porous surface, the brass chest-piece ensures perfect surface hygiene. 4_ Two internal channels run parallel in the stethoscope tubing. This prevents the friction noises caused by two separate tubes. 5_ Through the separately integrated spring in the tube, there is no acoustic loss from the chest-piece to the ear. 6_ The ergonomically designed, super soft ear tips create an excellent acoustic seal against external noise interference and maximize wearer comfort and fit. 7_ The standard 15° inclined binurals can be individually adapted to the ear canal characteristics of the user.