In order to use this custom ZeroLemon accessory, you will have to take out the stock battery of your Note 3 and put the ZeroLemon one in its place. Due to its enormous size you can't just put your stock rear cover back on – you'll have to use the universal fit case which is included in the ZeroLemon set. Well, yes, this will make your Note 3 noticeably thicker, but the 10,000mAh battery will most probably double or even triple the battery life of your Samsung phablet.
The Note 3 is not a small device, but when outfitted with the ZeroLemon 10,000mAh battery and case, it looks quite huge. Fortunately, the set comes with a belt clip holster, which doubles as a kickstand. The ZeroLemon case also offers some improved resilience for the battery and the Note 3 itself. The case comes with double polycarbonate and a single thermoplastic polyurethane protective layers, which will allegedly fully absorb the major impacts your device might experience. There are built-in protective tabs for the SPen stylus and the microUSB port on the bottom as well.
The ZeroLemon 10,000mAh Tri-Cell Extended Battery case set is currently available on Amazon for $59.99 and comes with a 180-day warranty (link provided at the source). It is compatible with all versions of the Samsung Galaxy Note 3 - N9000, N9005, Sm-n900t, Sm-n900w8, Sm-n900p, Sm-n900v and Sm-n900a.
source: Amazon, ZeroLemon via GSMArena