Abstract: A tool for the installation of a sink flange and garbage disposal mounting flange assembly in the drain opening of a sink, such tool including a generally U-shaped member with the tops of each side thereof extending outward, a shaft member affixed to a central portion of the U-shaped member extending between the sides thereof, such shaft receiving the mounting flange assembly and having a threaded portion passed through the drain opening in the sink in which is positioned the sink flange and on which shaft is positioned a retention member, such shaft passing through an aperture centrally defined in such retention member with a handle member having a threaded engagement aperture to be screwed down on the shaft to retain the sink flange and garbage disposal mounting flange structure in place during installation thereof.