Abstract: A seat rubber mounted onto a suspension component including: an outer peripheral plate-shaped part extending along a receiving part of the suspension to receive a coil spring; an annular curving part defined by a radially inner portion of the outer peripheral plate-shaped part rising along a riser part of the suspension; a center projecting part inserted into a positioning hole of the suspension while being positioned inside the outer peripheral plate-shaped part and projecting from a distal end of the curving part toward its proximal end; an annular groove provided between the curving part and the center projecting part while receiving the riser part; and a flat-plate shaped reinforcing member embedded in the outer peripheral plate-shaped part around the riser part outwardly away from the curving part so as to disperse and transmit an input from the coil spring to the receiving part.