blood pressure monitor
Device composed of an armlet and a pressure gauge; it is used to measure diastolic (heart dilatation) and systolic (heart contraction) pressure.
pneumatic armlet 
Device that wraps around the arm and squeezes the humeral artery; blood pressure is measured when the air is let out of the armlet.
pressure control valve 
Valve used to expel air from the armlet to reduce pressure.