A wheel includes a rim having two sidewalls and a groove is defined between the two sidewalls. A plurality of apertures and a valve receiving aperture are respectively defined through the rim. A seal member is located in the groove and has a hole defined therethrough. The hole is located in alignment with the valve receiving aperture. Two sides of the seal member are located on tops of the two sidewalls of the rim so that when a tire is engaged with the groove, the two sides of the seal member on the tops of the two sidewalls are respectively compressed by the tire.