Product review (1 stars): Keep looking
I bought two of these several months ago, from Amazon. One works. The other has faulty battery contacts ... once I attempted to fix that, the display showed nothing but numeral 8s all across. Efforts to clear or reset prove fruitless. Both of the devices wore out their batteries in about six months. These are, or should be, very low-current devices, since they have a small LCD display and no illumination or alarm feature, and those lithium batteries are very long lived, normally. This device is utter crap. I won't buy another. Hugely overpriced as well. With a chip like that, cost to manufacture probably is less than half a dollar. Even if yours keeps working, you can't reset or adjust it without the instructions in hand, because the user interface was designed by sadists. Google the product name and you can find the manual online.