Amazon calculates a product’s star ratings using a machine learned model instead of a raw data average. The machine learned model takes into account factors including: the age of a review, helpfulness votes by customers and whether the reviews are from verified purchases.
I recently purchased this monitor and it’s fabulous. Not only does it give easy and clear readings, it fits the whole family, from 44 to 3 years old! It’s comfortable to wear and very simple to use. It’s great for my daughter who has a heart condition that requires occasional monitoring. Highly recommended A+++++++
It is simple to use and gave us both a reading in the expected zone. This is not something you would normally need at home but given the spread of the flu virus and the fact people can be quite badly affected without realising it, this monitor is a good indicator of whether to seek medical attention.