A re-usable outer shell comprising: a front and back waist region having uppermost and lowermost edges; and a crotch region interposed between the front and back waist region, wherein the uppermost edges of the waist region form a waist opening and the lowermost edges of the waist region together with lateral extremities of the crotch region form two oppositely disposed leg openings; and wherein at least the body-facing surface of the crotch region is adapted for receiving an absorbent insert; and wherein at least a portion of said crotch region comprises a stiffening element, characterized in that the stiffening element is removably coupled to, or integrally formed with, said outer shell and extends substantially parallel to a longitudinal centerline (y) of said outer shell over a length that is less than the total length of said outer shell in laid out flat state, and in that said stiffening element has a maximum width (W MAX) and a minimum width (W MIN) wherein the maximum width (W MAX) is greater or equal to the minimum width (W MIN), and the crotch region of the outer shell has a maximum width (W C) wherein W MAX is less than 70% of W C, and wherein the stiffening element is substantially symmetric about the longitudinal centerline (y) and extends substantially therealong, and in a central zone of the crotch region, such that the 30% or more width difference between W C and W MAX is substantially divided into two equal amounts at either side outboard of the stiffening element, and wherein the stiffening element has a higher resistance to bending compared to any other position and/or element of the outer shell. a front and back waist region having uppermost and lowermost edges; and a crotch region interposed between the front and back waist region, wherein the uppermost edges of the waist region form a waist opening and the lowermost edges of the waist region together with lateral extremities of the crotch region form two oppositely disposed leg openings; and wherein at least the body-facing surface of the crotch region is adapted for receiving an absorbent insert; and wherein at least a portion of said crotch region comprises a stiffening element, characterized in that the stiffening element is removably coupled to, or integrally formed with, said outer shell and extends substantially parallel to a longitudinal centerline (y) of said outer shell over a length that is less than the total length of said outer shell in laid out flat state, and in that said stiffening element has a maximum width (W MAX) and a minimum width (W MIN) wherein the maximum width (W MAX) is greater or equal to the minimum width (W MIN), and the crotch region of the outer shell has a maximum width (W C) wherein W MAX is less than 70% of W C, and wherein the stiffening element is substantially symmetric about the longitudinal centerline (y) and extends substantially therealong, and in a central zone of the crotch region, such that the 30% or more width difference between W C and W MAX is substantially divided into two equal amounts at either side outboard of the stiffening element, and wherein the stiffening element has a higher resistance to bending compared to any other position and/or element of the outer shell.