PURPOSE: To facilitate variation of a shape without varying mounting original to a pure rear spoiler and simplify return of a shape to the original state by fixing an auxiliary spoiler to the pure rear spoiler by means of a double coated tape.

CONSTITUTION: Formerly, in variation of the design of the pure rear spoiler of an automobile and variation of an aerodynamic effect, after a pure rear spoiler is removed, a rear spoiler in a different shape is newly mounted. Thus, processing of a screw hole in which the rear spoiler is heretofore mounted is needed and it takes a long time to mount and demount. Therefore, to eliminate a defect, a pure rear spoiler 1 is covered with an auxiliary spoiler and fixing thereof is effected by means of a double coated tape 3. This method facilitates variation of a shape without varying mounting original to the pure rear spoiler.