Look, to confirm whether it is accurate or not, it must be tested with a corresponding Police device. Cheap, cheap construction but clear, fits like a glove if you gather with a group, drink your guts out and want to see for fun how drunk everyone is. That's it.

I didn't expect it to have accuracy in its measurements, but it gives me the feeling that the measurements are completely random

The price limits to achieve a green, orange, or red price are not mentioned in the brochure or anywhere else.