A retention grommet has a bottom grommet and a top grommet. A floor cover retention flange extends radially outwardly from an outer sidewall of the bottom grommet. The outer sidewall extends upwardly from the retention flange to a hinge plane of the bottom grommet. Plural fingers are disposed around the bottom grommet axis so as to be angularly spaced from each other and an inner surface of the outer sidewall. An upper end of each finger is joined to the outer sidewall at the hinge plane. Near a free, downwardly displaced end of each finger, a retention bead is formed to have an upwardly and radially outwardly inclined surface. This surface engages a retention post of any of several vehicle foot well affixation devices, one of which is adapted to be affixed to a carpeted surface and another of which is adapted to be affixed to a smooth surface.