Product review (2 stars): doesn't meet manufacturer's specs
I tested 6 of these units in 2 different refrigerators. Manufacturer's user guide states they will run for 30-45 days, and then a red light will indicate the need for a recharge.

However, after charging them fully, all 6 had run down between 2 and 3 weeks, and NONE of them displayed the red light to show that they had quit. This was not due to a colder than average frig, since I run one of these refrigerators at a higher than normal temperature (44-48 degrees).

They do seem to keep food fresher, but are high maintenance. If the internal rechargeable battery performs that poorly, who knows how long it might last?

I sent all 6 back and am now looking for one with better performance.