It could not be simpler, but really handy +++

Always dropped when it should not be by the battery of my Samsung Galaxy S3 18 months of age, I bought a replacement battery and this little battery charger. So I always have a second charged battery. Concerning product delivery, no problem time and quality.
The case is really very simple (well thought functionality and just necessary):
- A place to put the battery charging (battery obvious position to find with visible connections)
- A handy little shutter to carry all "case + battery charge" in a bag when traveling, and the second battery "trolling" not without protection,
- A small connector "female" to connect the power cable when purchasing the Samsung S3 (no cable provided with the case)
- A small LED serving as a charging indicator:
Red: In charging,
Green: Charged. The only problem I found is that the light goes Green before reaching a 100% load. Why, I do not know. I got during my first tests of battery charge levels (measured on the Samsung) between 85 and 95%. With this, now I leave plugged longer the case, even if the light is passed to GREEN, and now, I get loads of levels of around 98%. Never found 100%.
The added benefit of having this housing and an additional battery is that I can achieve more optimal battery charge (discharge large battery approx. 10%), which seems to be a prerequisite for its durability in use.
So very happy with this purchase, but one less star for not reaching the level of 100% load.