The Keysight U4324A
flying lead probe is a Keysight probing solution provided for the U4301A PCIe
Gen3 Protocol Analyser module. Each Flying Lead probe consists of five cables
on one end and a pod on the other end. Four of the five wires are used to
capture a PCI Express differential signal. The fifth wire is provided for
connecting the probe to an optional external reference clock on the DUT.