This product is highly accurate and provides good value for its cost; however, it does not come with batteries included. Nevertheless, it is important to note that the product arrives pre-calibrated. If batteries were provided, I would confidently rate it with 5/5 stars.
The batteries were bought from me.

The pH meter clearly recognizes the lower pH of water from reverse osmosis filtration. I am not able to verify the precision of the values, but they seem accurate based on my knowledge. The build quality is solid. Please note that batteries are not included. I would definitely buy another one as it offers good value for money.
The estimated delivery date initially provided was two weeks later than the actual arrival date, which was a pleasant surprise. Good job Banggood!