3M Littmann 2160 Black Master Cardiology Stethoscope 27 Length, Provides the best acoustics Littmann Master Cardiology stethoscopes offer with significant improvement in low frequency responses. Solid stainless steel single-sided chest piece. Headset assembly with double lumen binaural, is permanently set at an anatomically correct angle to minimize air leaks and prevent loosening over time. Two tubes in one design reduces noise from two tubes rubbing together. Soft Sealing ear tips ensure excellent acoustical seal in the ear canal with maximum comfort. Patented Littmann Special Procedure Adapter Allows auscultation and difficult body parts and pediatric, or emaciated patient.