Abstract: A clamping ring having a clamping ring flange for use with at least first and second different configurations of drain bases to permit the rotation of the clamping ring flange relative to the drain flange of both type “A” and type “B” drain bases. The clamping ring flange includes a plurality of first aperture portions, each of which has a second elongated arcuate slot portion extending in a counterclockwise direction from the first aperture portion and a third elongated arcuate slot portion extending in a clockwise direction from the first aperture portion, at different distances from the center of a central flange aperture with one corresponding to the positions of threaded apertures in the type “A” drain base and the other corresponding to the positions of the threaded apertures in the type “B” drain base.