The back covers the battery, and contains the serial number. Inside, there is a floating directional pad, two face buttons (A and B), Start and Select buttons, as well as a brightness button, the speaker, and the lights. On the top, there is also two shoulder buttons (L and R). The only feature removed from the original Game Boy Advance was the headphone jack on the back, but a Headphone Adapter and special Game Boy Advance SP Headphones were sold.