Opening device (3, 3') for a package having a designated pour opening and being filled with a pourable product; the opening device (3, 3') comprises a contact portion and a closing element detachably and/or rupturably attached to the contact portion and configured to close and/or cover the designated pour opening; wherein the closing element comprises: - a main wall detachably and/or rupturably attached to the contact portion; and - a pulling device connected to the main wall and configured to allow for the exertion of a separation force on the main wall so as to detach the closing element from the contact portion; wherein the pulling device comprises: - a plurality of leg elements connected to and transversally extending from the main wall; and - a coupling structure connected to the plurality of leg elements; wherein each leg element comprises: - an elongated pillar extending along a longitudinal axis, having a first end and a second end, and being connected to the main wall at the first end and to the coupling structure at the second end; and characterized in that the pulling device further comprises at least one stiffening rib connected to a connection portion of the pillar; wherein each stiffening rib is integrally connected to the main wall; wherein each pillar consists of the connection portion and a further portion extending from the respective connection portion and to the respective second end; wherein each connection portion comprises the respective first end and has a first extension along the respective longitudinal axis that equals or is less than half of a second extension along the respective longitudinal axis of the respective pillar from the first end to the second end; wherein each first extension and each second extension are measured along a direction orthogonal to the main wall. the opening device (3, 3') comprises a contact portion and a closing element detachably and/or rupturably attached to the contact portion and configured to close and/or cover the designated pour opening; wherein the closing element comprises: - a main wall detachably and/or rupturably attached to the contact portion; and - a pulling device connected to the main wall and configured to allow for the exertion of a separation force on the main wall so as to detach the closing element from the contact portion; - a main wall detachably and/or rupturably attached to the contact portion; and - a pulling device connected to the main wall and configured to allow for the exertion of a separation force on the main wall so as to detach the closing element from the contact portion; wherein the pulling device comprises: - a plurality of leg elements connected to and transversally extending from the main wall; and - a coupling structure connected to the plurality of leg elements; - a plurality of leg elements connected to and transversally extending from the main wall; and - a coupling structure connected to the plurality of leg elements; wherein each leg element comprises: - an elongated pillar extending along a longitudinal axis, having a first end and a second end, and being connected to the main wall at the first end and to the coupling structure at the second end; and - an elongated pillar extending along a longitudinal axis, having a first end and a second end, and being connected to the main wall at the first end and to the coupling structure at the second end; and characterized in that the pulling device further comprises at least one stiffening rib connected to a connection portion of the pillar; wherein each stiffening rib is integrally connected to the main wall; wherein each pillar consists of the connection portion and a further portion extending from the respective connection portion and to the respective second end; wherein each connection portion comprises the respective first end and has a first extension along the respective longitudinal axis that equals or is less than half of a second extension along the respective longitudinal axis of the respective pillar from the first end to the second end; wherein each first extension and each second extension are measured along a direction orthogonal to the main wall.