Embedded Board eXpandable (EBX) is a standardized computer form factor.
This format was created for embedded computer systems by a consortium including Motorola and Ampro. EBX systems typically were embedded PowerPC or PowerQUICC based.
The system board is specified as 8 × 5.75 inches (203 × 146 mm). It incorporates a PC/104-Plus connection subset for peripheral expansion. Optional connectors for PCMCIA are allowed.
http://www.pc104.org/ebx_specs.php