The back is the same sort of curved, removable plastic battery cover seen in most budget mobile phones. (techradar.com)
The textured plastic battery cover feels nice in the hand and it's got a «grippy - ish» feel I like and it is again very similar to the Galaxy S II. (tmonews.com)
The Galaxy J3 has a peel - off plastic battery cover, hiding the removable battery, the microSIM slot and the microSD slot. (techradar.com)