Note:One point is to explain the impedance problem of the coupled isolating transformer: this transformer is 600 ohm: 600 ohm audio transformer, the impedance 600 ohm refers to the AC impedance, and the actual multimeter is a DC impedance, at about 100 ohm.

Frequency Range: 50Hz--100KHz
AC Impedance Ratio: about 600 : 600 ohm
Inductance: about 1.6H
Withstand Voltage: 1000V above

Package included：5 pcs*600 ohm Toroidal Transformer