This keyboard was featured as a point of comparison in my review of the Unicomp New Model M.
The Unicomp Ultra Classic (PC) and Unicomp SpaceSaver M (Mac) are compact-profile full-size Model Ms featuring the thinnest side bezels ever put to a Model M design. Like its EnduraPro sibling, the SpaceSaver family are produced using the same moulds formerly used to make IBM 5576-C01 keyboards in the '90s. Unlike the EnduraPro or 5576-C01, these do not feature any integrated pointing stick. The Ultra Classic was also previously known as simply the SpaceSaver and should not be confused with the IBM Space Saving Keyboard (SSK) or Space Saver Keyboard (Model M4-1).