BNBL (Binary Nitro Button Layout) are [jnlib layout files|Jnlib Layout File Format] that define the locations of buttons on the touch screen. It has a file signature of {{"JNBL"}}.

Following the file header is a series of layout elements. This is structured as follows:

||Offset||Type||Meaning
| 0x00   | u16 | X coordinate/origin
| 0x02   | u16 | Y coordinate/origin
| 0x04   | u8  | Width
| 0x05   | u8  | Height