Bought these a couple of months ago. Both worked well for 1 month. Then, the “on” button to initiate charge died on 1 unit. Customer service would not accept Woot receipt as proof of purchase. Now I have 1 of these wireless power banks that works properly. The other has to be plugged into the wall on its power cord to use as charger, defeating the purpose of having a wireless charger. Buyer beware.