The 4I66CR is a stackable PC/104-plus card that combines a 100BaseT Ethernet MAC with a 4 port switch.  The 4I66CR makes it easy to connect multiple embedded system cards without the awkward power or mechanical problems with consumer type Ethernet switches.  The 4 Ethernet ports support autonegotiation allowing connections with half and full duplex, 10 and 100 BaseT devices plus auto MDX, eliminating the need for crossover cables.  The Ethernet MAC is a National Semiconductor DP83816 which has drivers available for most operating systems.  The switch has sufficient bandwidth to support full duplex wire speed connections on all ports. The 4I66 CR Model uses Molex connectors instead of RJ45 jacks. The NOJ1 option leaves the PC104-Plus connector uninstalled. The -CC option indicates the conformal coated option.