What is it?

Aneroid Sphygmomanometer, the device is composed of a dial, pump, cuff and valve. Once the cuff is inflated, it applies pressure to the brachial artery.

What is it used for?

A stethoscope is used to listen to arterial blood flow sounds, an instrument for measuring blood pressure, typically consisting of an inflatable rubber cuff which is applied to the arm and connected to a column of mercury next to a graduated scale, enabling the determination of systolic and diastolic blood pressure by increasing and gradually releasing the pressure in the cuff.