Package material comprising a multilayer material structure having one or more layers of plastic laminate, the package material comprising: - a first side and a second side opposite the first side and a penetration area defined in the multilayer material structure; - at least one weakening line in the multilayer material structure extending from the penetration area and adapted to provide an opening in the multilayer material structure when being ruptured; - an opening device, the plastic opening device comprising: a first portion attached to the first side; a second portion attached to the second side; a material bridge penetrating through the penetration area and connecting the first portion to the second portion; wherein the second portion at least partly covers the penetration area and further comprises a guiding portion (35, 36) extending from the penetration area adjacent to the at least one weakening line as to facilitate rupturing substantially along the at least one weakening line wherein the at least one weakening line comprise a first and second weakening lines, each of them extending from the penetration area creating an area on the multilayer material structure in between, said area forming the opening, characterized in that the guiding portion (35, 36) comprises at least two leg sections arranged on the area and having an edge, said edge arranged at least partially substantially parallel to the corresponding one of the first and second weakening lines, wherein the second portion (4, 46) covers partly the area forming the opening and the area in between the two leg sections. - a first side and a second side opposite the first side and a penetration area defined in the multilayer material structure; - at least one weakening line in the multilayer material structure extending from the penetration area and adapted to provide an opening in the multilayer material structure when being ruptured; - an opening device, the plastic opening device comprising: a first portion attached to the first side; a second portion attached to the second side; a material bridge penetrating through the penetration area and connecting the first portion to the second portion; a first portion attached to the first side; a second portion attached to the second side; a material bridge penetrating through the penetration area and connecting the first portion to the second portion; wherein the second portion at least partly covers the penetration area and further comprises a guiding portion (35, 36) extending from the penetration area adjacent to the at least one weakening line as to facilitate rupturing substantially along the at least one weakening line wherein the at least one weakening line comprise a first and second weakening lines, each of them extending from the penetration area creating an area on the multilayer material structure in between, said area forming the opening, characterized in that the guiding portion (35, 36) comprises at least two leg sections arranged on the area and having an edge, said edge arranged at least partially substantially parallel to the corresponding one of the first and second weakening lines, wherein the second portion (4, 46) covers partly the area forming the opening and the area in between the two leg sections.