The stethoscope is an acoustic medical device for auscultation, or listening to internal sounds of the human body. It typically has a small disc-shaped resonator that is placed against the skin and one or two tubes connected to two earpieces. A stethoscope can be used to listen to the sounds made by the heart, lungs or intestines, as well as blood flow in arteries and veins. In combination with a manual sphygmomanometer, it is commonly used when measuring blood pressure.