The 3U CompactPCI Express backplane comes in four slots. Versions in PXI Express are also available.
Complies to latest EXP 0 specifications
PCI Express over CompactPCI form factor
Backwards compatibility to CompactPCI
Contains (one) system, (one) Type 1, (two) Type 2 slots
System slot-two ZD and one enriched 2mm HM
Type 2-one ZD and the one enriched 2mm HM