The battery charger works well and it sturdily built. I bought it to charge batteries for my Samsung Galaxy Ace 2 I8160 phone.
My only criticism, and the reason for deducting one star, is that the recessed area within the charger into which the battery fits is slightly narrower that my battery so that, when inserted into this space the battery extends beyond the width of the charger. There is no real problem with this, it's just that inserting my battery into it feels a little fiddly.
I imagine the dimensions of the charger were chosen to suit Galaxy S3 Mini batteries (I don't have an S3 Mini so this is speculation).