Which heart rate monitor to choose?

Question

Samsung

I decided to get myself a heart rate monitor. Pure heart rate monitor, without a watch, connection to the phone and other things. From everything I found, Sigma Sport PC 3.11 is suitable, but I don’t like their size, and the lack of backlighting confuses me.
In appearance, I would like something like Garmin Vivofit Bundle HRM or Samsung Gear Fit, but without excess: only a heart rate monitor. Well, you can also have an indicator that will somehow notify you about the excess of the pulse - vibration, indicator light or sound signal.
I look at the Chinese, so they sell pedometers or activity trackers under the guise of heart rate monitors