A package material may include one or more layers of plastic laminate, a first side, a second side and a penetration area. A weakening line may extend from the penetration area and may provide an opening area in the package material. The package material may include a plastic opening device, with a first and second portion attached to the first and second side, respectively, and a material bridge penetrating through the penetration area. The second portion may cover at least partly the penetration area and may include a guiding portion 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.