When taking your blood pressure a wrist blood pressure monitor is pretty accurate.
However the arm blood pressure monitor is better and more accurate at getting the correct blood pressure reading.
I did notice that when I used a wrist blood pressure monitor that the blood pressure reading was off just a little bit when I took my blood pressure using the arm blood pressure monitor.
So I would recommend using the blood pressure monitor that goes on the wrist to get a more accurate blood pressure reading.
But it's a good thing to have the wrist blood pressure monitor as well.
But for the most accurate results use the arm blood pressure monitor.
Also make sure you're calm and keep your body and arm still and avoid talking while you take the blood pressure reading.