I purchased the “DROK 100136 12 Volt DC Car Digital Electric Clock Fahrenheit °F Temperature Voltage Measurement White LED Gauge Panel Meter 18B20 Sensor Probe” from Amazon.  I need 4 digit resolution.  The unit I received has two problems:

1) It is almost 0.1 volts off correct reading according to our HP34401A DVM.

2) It will not update the LSD (Lowest Significant Digit) to the right.  It remains at zero 90% of the time.  When it is not at zero it rapidly bounces in a random fashion, such as 2, then 7, then 4…usually settling on zero.  If this is typical of this unit it is a 3-digit display not a four digit.

If this is typical I will return it, please advise.