1. To remove the SIM card, open the back cover of the device using the notch located on the left of the cover. 
   Note: Your device will come with the Micro-SIM card preinstalled.
   
2. Remove the battery using the notch located at the bottom of the battery.
   
3. Slide the SIM card out of or into the SIM card slot.
   
4. Insert the battery, making sure the gold contacts touch.
   
5. Reinsert the back cover of the device, pushing at the edges until it snaps into place. Firmly close the battery cover to ensure the device is water-resistant and dust proof
   Note: The AT&T Unite Explore meets US MIL-STD-810G for shock-resistance. Certified IP65 for protection against dust and water jets. Device will not operate under water and should be dried as quickly as possible when wet. Shock-resistant when dropped from ≤ 4 ft onto flat surface. Device may not perform as shown in all extreme conditions.
   
6. To attach an external antenna, pop open and pull open the antenna port door, then insert the antenna into the port. The antenna is sold separately.
   Note: For more information, see the NETGEAR support article: External Antennas for AirCard products. When not using an external antenna firmly close the accessory ports and battery cover to ensure the device is water-resistant and dust proof.
   
7. If a SIM is not in the device the Missing SIM screen will display.