I was extremely disappointed in this product. I know the price of the product was inexpensive but I expected it to last more than one day. There were several problems associated with this product. First there were no instructions. Secondly, it took over 8 hours for the initial charge of the product. There is no way of telling how much charge is left in the portable charger after using it. After the initial charge I used it to charge my Motorola Droid X smartphone. The battery on the phone showed that there was 30% charge left on its battery. After using the portable charger, it quit after only charging the smartphone to 50%. I plugged the battery pack in to recharge and then tried to use it on my phone again. After only a few minutes I heard a loud pop from the battery pack, smelled something burning and the battery pack was extremely hot and no longer worked. This could have damaged my phone or even worse been a fire hazard. I bought this product and another more expensive battery pack (KMAX-807) to test before I gave them as Christmas gifts to my family and friends who are heavy cell phone users. The KMAX-807 has performed as advertised. Imagine how embarrassed I would have been if one of my family or friends experienced my same problems.