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Torx screwdriver heads (T3 & T5) A small flathead tool The SIM card tray is located inside the phone below the volume buttons on the side. Reassemble the phone next. Take the battery out of the bottom half portion of your phone. Note that this is likely to damage one or both of the battery leads.

Summary:
You will need the following tools on hand: Take out the SIM card tray from your Motorola Droid Ultra. Slot the new battery into place and reattach the leads. Use a flathead tool to gently pry and remove the flat square battery, if you want to remove it, but not replace it.