A depth-extendable display unit consists of at least two essentially identical standard depth display tracks for forming a single depth-extended display track from one of the tracks and at least one section of another of the tracks. Each track has a front section, a breakaway back section with a rear connector at the rear thereof, and an interconnected series of breakaway intermediate sections connecting the front and back sections. The intermediate and back sections define at the front thereof forward connectors for engagement with the rear connectors, the forward connectors being exposed for engagement by breaking away of the immediately forward section.