A filler panel/horizontal manager for a rack includes two latching regions that mirror each other. The latching regions include a pair of guide posts configured to enter both round-shaped and square-shaped holes and guide the filler panel into a rack. The latching region further includes a pair of locator walls configured to enter square shaped holes along with the guide posts to guide the filler panel into a rack. Each latching region includes one or more latching members having surfaces for engaging a railing of a rack. At least one pair of latching members includes an angled stepped surface configured to engage railings of different thicknesses. One or more outwardly extending cable management elements may be associated with a front face of the filler panel/horizontal manager to facilitate wire/cable management functionalities.