A sphygmomanometer, also known as a blood pressure monitor is a device used to measure blood pressure. It is composed of an inflatable cuff to collapse and then release the artery under the cuff in a controlled manner.
For a manual blood pressure measurement, the nurse or technician places a stethoscope over the major artery in your upper arm (brachial artery) to listen to blood flow. The cuff is inflated with a small hand pump. As the cuff inflates, it squeezes your arm. Blood flow through the artery stops for a moment.