The invention relates to electrical apparatus of substantial size which includes an outer container and a unit insertable in the container which can be readily withdrawn for the purposes of repair or inspection. The insertable unit consists of an oilcooled lower part and an upper control part. The container has an internal shoulder which is engaged by the upper control part of the unit when the unit is inserted in the container. Struts pivotally connected to the lower end of the unit serve to guide the unit during its withdrawal from the container and to serve as support legs for the unit after it is withdrawn. When the unit is in its withdrawn position the struts rest on the internal shoulder of the container. The struts fold under the unit when it is inserted into the container.