A re-usable outer shell comprising: a front (F) and back (B) waist region having uppermost and lowermost edges; and a crotch region (C) 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 (C) form two oppositely disposed leg openings; and wherein at least the body-facing surface of the crotch region (C) is adapted for receiving an absorbent insert ; and wherein at least a portion of said crotch region (C) comprises a stiffening element (SE), characterized in that the stiffening element (SE) 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 (SE) 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 (C) 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 (SE) is substantially symmetric about the longitudinal centerline (y) and extends substantially therealong, and in a central zone of the crotch region (C), 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 (SE), and wherein the stiffening element (SE) has a higher resistance to bending compared to any other position and/or element of the outer shell. a front (F) and back (B) waist region having uppermost and lowermost edges; and a crotch region (C) 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 (C) form two oppositely disposed leg openings; and wherein at least the body-facing surface of the crotch region (C) is adapted for receiving an absorbent insert ; and wherein at least a portion of said crotch region (C) comprises a stiffening element (SE), characterized in that the stiffening element (SE) 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 (SE) 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 (C) 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 (SE) is substantially symmetric about the longitudinal centerline (y) and extends substantially therealong, and in a central zone of the crotch region (C), 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 (SE), and wherein the stiffening element (SE) has a higher resistance to bending compared to any other position and/or element of the outer shell. <EOS>