The present application relates to a device for opening a line, particularly the line of a blood tube or blood bag system, wherein the line has a sealing element that blocks the line passage, wherein the device comprises at least one opening unit that is configured such that the same exerts a force acting upon the line from the exterior, whereby the sealing element is pressed together and the line is opened. The opening unit is contoured such that the line can be inserted into the opening unit only such that the force acting upon the line is exerted exclusively, or at least also in the region, in which the locking element is located.
