N2790A - 

Keysight High-voltage Differential Active Probes N2790A & N2791A
These high-voltage differential probes are for making, safely and accurately, floating measurements in power electronics circuits. They enable conventional earth-grounded Keysight oscilloscopes to be used for floating signal measurements (i.e. where neither point of measurement is at earth ground). Selectable attenuation settings make for highly versatile probes which come with tip accessories to facilitate working with large and small components in tight spaces.