[Hugh R]

Amazon, many suppliers. If you have a 4S, check the two bottom screws to see if they are a philips or star pattern. I order the battery with a kit that contained the right screw drivers. Make sure the battery is for a 4 or 4S, there is a difference. Look at a couple of youtube videos on the subject. If its a 4S, pay particular attention to a tiny antenna shield under the top battery connector screw, its easily for it to fly off and you'll never find it.