Pico Technology | TA044 7000 V active differential probe
Differential High Voltage Probes | Measure Floating Circuit
Oscilloscope Probes, Universal 10X 100MHZ 700V High Voltage Differential Oscilloscope Clip Probes, USB Portable Oscilloscope Test Kit with Sorage Case for High Voltage: Amazon.com: Industrial & Scientific
Micsig MDP1500 High Voltage Differential Probe Kit, 3.5ns Rise Time 10 – SainSmart.com