GROMMET

A first grommet includes a ring-shaped seal portion into which a peripheral edge of an attachment hole Pa is fit, and a joining piece serving as a first joining portion. A second grommet includes a holding portion serving as a second joining portion that is joined to the joining piece . The seal portion includes a brim portion serving as a first flange portion that is engaged with a side surface Pc of a vehicle body panel P, and a lip portion serving as a second flange portion that is engaged with a side surface Pb of the vehicle body panel P. Also, the joining piece is formed on the inner side in the radial direction of the lip portion