PC/104 is a embedded computer standard, intended for specialized embedded computing environments where applications depend on reliable data acquisition despite an often extreme enviroment. The PC/104 form factor has no backplane and allows modules to stack together like building blocks, which is more rugged than typical bus connections in PCs.
The PC/104-Plus form factor adds support for the PCI bus, in the addition to the ISA bus of the PC/104 standard.
Examples of PC/104-Plus Cards
AceXtreme MIL-STD-1553 PC/104-Plus (BU-67105C)
AceXtreme MIL-STD-1553 & ARINC 429 PC/104-Plus Card (BU-67109C)
MIL-STD-1553 BC/RT/MT PC/104-Plus Card (BU-65578C)