Review on Dlyfull LCD Battery Tester - Universal Checker For AA AAA C D 9V CR2032 CR123A & More, 2X AAA Batteries Included by David Olson

After 2 years experience, I just now wrote this email to the company:I have used a Dlyfull B2 Universal LCD Battery Tester for several years. It seems well made of reasonable materials. It seems to be a precise instrument, but I question its accuracy in terms of the ranges for "POOR” "WEAK” and "GOOD. Every battery that I have taken out of use in alarms, monitors, clocks, and lights (that had recently quit working) still tested into the "GOOD” range, by 2-5 lines/bars. So, for me, the "WEAK” and "POOR” ranges are useless, because I will never have a battery whose voltage is that low. I have recorded the voltage of new and used, nominally 1.5 Volt batteries, and the associated number of bars in the "GOOD” range of the tester:8 bars into GOOD = 1.59 V7 bars into GOOD = 1.49 V6 bars into GOOD = 1.45 – 1.47 V4 bars into GOOD = 1.32 V3 bars into GOOD = 1.25 - 1.29 VAre the above equivalencies within tolerances of the design for the B2 Tester?I have found that most fire, smoke, carbon monoxide alarms, wall clocks and other items quit working at around 1.3-1.5 volt. So why would you design a tester to indicate that even lower voltage batteries are still "GOOD"?I have come to the conclusion that the difference between a fresh new battery and a useless battery is indicated within the 8 bars of the "GOOD" range.