SEALING DEVICE, AND ROLLING BEARING AND HUB UNIT INCORPORATING THE SEALING UNIT

The seal member 7a with its base end connected to the metal core 5 has three seal lips 14, 15a, 16a. Of these, the intermediate seal lip 15a in the intermediate position is provided that the thickness of the tip end is d1, and that the thickness of the base end is d2. The innermost inner seal lip 16a is provided that the thickness of tip end is D1 and that thickness of the base end is D2. In this case, at least part of the base end of the intermediate seal lip 15a and inner seal lip 16a has its thickness regulated to be 0.2.d1