Abstract: A conductor support is provided for use with high voltage electrical devices having mounting walls with apertures formed therein through which electrical conductors pass. The conductor support is formed of first and second channel members sequentially inserted in the mounting wall aperture. The first channel member includes walls bendable toward and away from each other, corresponding to collapsed and expanded configurations of the first channel member, respectively. The first channel member is collapsed to take on a reduced cross sectional area, and is inserted through the aperture of the mounting wall. The first channel member includes retaining members, such as notches or grooves, for engaging the mounting wall. After insertion, the first channel member is expanded to bring the retaining members into engagement with the mounting wall.