Abstract: A sealing system for sealing the space between relatively rotatable members comprising a rigid support element and an annular elastomeric sealing element having an internal radial annular lip extending radially and axially from an annular root portion of the elastomeric element. The annular lip has a radial section of generally V-shaped cross section, having its vertex located obliquely with respect to the axis of the elastomeric element and comprising two portions of reduced cross section, one of the portions corresponding to the root portion and the other to the vertex of the V. Portions of reduced cross section divide the annular lip into first and second sections operable to engage with corresponding sealing surfaces on one of the members and having sufficient flexibility to hingedly connect the sections to one another and to the root portion.