A rack adapting device for an electronic equipment rack is disclosed. The electronic equipment rack is configured to house first electronic equipment modules having a first module width between left and right equipment supports laterally spaced apart from one another by a rack housing width corresponding to the first module width. The rack adapting device is configured to adapt the electronic equipment rack to house a plurality of second electronic equipment modules having a second module width and comprises: an adapter body; a plurality of rack-engaging features disposed on a first lateral side thereof and configured to engage rack mounting features of one of the left and right equipment supports; and a plurality of adapter mounting features disposed on a second lateral side such that, in use, the second electronic equipment modules are mounted between the rack adapting device and an other one of the left and right equipment supports.