I have the 2100 mah extended battery and the Defender fits. I will say that I've accidentally broken two of the pieces that clasp together on one side from carelessly taking it apart so be careful. You can use your fingernail to depress the clasp to take it apart. Although bulky, it is a nice case and it keeps my mind at ease with the protection it gives. The screen protector takes some beauty out of the screen but I like the idea of the phone being sealed in from the outside. Also, while I'm not a fan of holstering enormous phones to my hip I did attach the holster to my bike to hold my phone while I ride. I hope this helps and ask more questions if you have any.