Working ok on installation, used it for the display of refrigerator along with temperature indication and alarm of freezer and chiller compartments. Appearance nice, clock accuracy good (seen for 24 hrs), temperature and voltage indication ok, has provision to adjust if required. Manual not provided with shipment. Here it is: Left button is selection of parameter, right button is for changing values. Press the left button of adjustment time - minutes, hour, date, month, year in succession. Next is error voltage calibration function [x.xU], the unit is 0.1V, plus or minus. Next is temperature correction [Ac: xx], again +or - . Further next is dd - (dd: 0) time + temperature + voltage, (dd: 1) time + voltage, (dd: 2 ) time + temperature, (dd: 3) Temperature + voltage. Next, dF, greater the value the longer the interval of display cycling. Do not set to 0. Next LL - brightness adjustment 1, 2, 3, AL parameters, set AL:1, dark after 7pm, bright after 6am morning.
Picture shown DS3231 but actual product is RX8025. It is conflict to each other