The PC/104 form factor (90x96 mm) is a standard for Single Board Computers issued by the homonymous consortium in the early 90s. It's still widely used today in embedded and industrial applications thanks to its compact form factor, robustness of the expansion connector and availability in the market of related expansion modules. PCI-104 and PC/104+ are further evolutions of the standard that integrate the PCI Bus in alternative or in addition to the ISA bus