SunJack 4000mAh Fast-Charge Battery

This charger ruined the battery on my Samsung S5 phone. I forget what the employee at the cellphone said exactly but, she did say the 2000mA output was too high for my phone. The larger version of this charger has variable voltage output which is the one you should use with your phone. It might be ok for an iPhone I don't know.What's really interesting is that, after sitting unused on a shelf for a few months, the battery swelled and broke the housing on the unit, (see pics). So it appears that plugging this battery pack into my phone not only ruined the phone, it ruined the battery pack.I'm still using the larger 8000mAh version. I just make sure to always double check to make sure I'm plugging my phone into the variable output, (5v 2.4A or 9v 1.67 A).

Need this to work on old family farm where wiring getting too old to be safe or reliable. Works nicely with solar charger we chose for cell phone and tablet.

Works like a charm to recharge my phone and batteries on the go.

3 only because I don't think it meets the requirement to be called a solar charger. As far as serving as a portable charger it is comparable to any other- as long as it is charged via electric source. I took it camping thinking if it was topped up first electrically I could keep it topped up by the sun. There were no instructions included with the charger, so I just charged it fully at home and left it on the dash of my car for solar charging. It didn't seem to charge via solar, just kept decreasing in charge percentage. So it was basically useless to me as a backup if there were no electricity.It is a nice, pretty little charger, but I already have portable chargers for that purpose. Buy this if you need a sleek little charger you charge up at home, but I would reconsider depending on it for charging off the grid.

I have smartphone n am a traveller n my phone gets dead frequently..its really good to have dis portable charger..its wit light weight..wit 4000 mAh...easy to carry anywhere..n charges my phone fast..for upto 3 times i can charge it full..

I used to miss out important official calls due to battery issues.. Then I opted for this sunjack battery charger.. It has really made my life easier.. Hope to get a good appraisal this time.

A compact and handy charger. Charges the phone well. Best part is its shape and size which makes it easy to carry with phone.You just need to connect via USB.Has good life. It is elegant and exquisite.

Worth buying.. good value for money. Your phone is never out of battery if you have this product.