The Tektronix P5102 probe is designed to isolate measurements from earth ground and also to isolate the common voltage between scope channels. The Tektronix probe P5102 provides isolated channel performance up to 1,000 VRMS CAT II when used with the Tektronix THS700 Series oscilloscopes. With the Tektronix high voltage probe P5102 and the Tektronix THS700 Series handheld digital storage oscilloscopes you have not only the isolation for the measurement from earth ground, but you also have full isolation between the two channels.