Rectangular seals constitute an alternative design to O-rings. Rectangular seals are employed in demanding applications such as aircraft actuators, e.g. ref. [1]. The seal edges are generally rounded, ref. [2]. As a consequence of the presence of filleted edges, the contact pressure exhibits Hertzian-type local bumps in its lateral zones; it remains almost flat in the central zone of the contact. The lateral bumps and the central flattish zone confer to the contact pressure distribution a camel-backed profile, see ref. [2], and ref. [3] for a similar axisymmetric problem. It is difficult to derive a rigorous, analytical expression of the contact pressure curve for the title problem. In fact, the analytical solution available for a rectangular punch with rounded edges indenting a half plane, e.g. ref. [4] and related bibliography, is exact only in the situation of a rigid punch indenting a deformable half plane, ref. [5], whereas in the title problem the punch (i.e., the seal) is flexible and the half plane (i.e., the counterface) is rigid. It has recently been shown in refs [5-7] that the unrealities of the above analytical solution may be corrected by combining the analytical solution with Fracture Mechanics (FM) results dealing with the stress singularities at the tip of a transverse crack in a strip of finite width. In this paper, an extension of formula (20) of ref. [5] is developed, that accounts for the combined effects of a) the presence of a filleted edge, and b) a finite seal width and height.