Interphase insulating spacers of the RMID type are designed for the isolated fixation of conductors and ground wires in overhead power lines (OPL) with voltages of 10–35 kV. They effectively limit the amplitude of oscillations and ensure the maintenance of necessary insulation distances between conductors of different phases, as well as between conductors and ground wires.

The design of RMID spacers lacks a rigid metal extender in the central part. An insulated fiberglass rod is used as the insulating element, which, if necessary, is equipped with ribs to provide the required leakage path length, significantly increasing the flexibility of the insulating element.

RMID spacers are manufactured according to technical specifications TU 3494-011-82442590-2009. Parameters of a specific model, such as structural length, insulation length, leakage path length, rated mechanical compressive strength, and allowable conductor diameter, vary depending on the design and should be selected in accordance with the requirements of the specific OPL.