A plunger intended for an inserter for an intrauterine device with a T-body, which plunger has a first end and a second end. The plunger's length in its longitudinal direction is substantially larger than the diameter of the cross-section perpendicular to the longitudinal direction. The plunger's cross-section is substantially circular. An opening (17) has been arranged in the plunger's longitudinal direction so that the opening's longitudinal axis is substantially the same as the plunger's longitudinal axis. The opening at the first end of the plunger is arranged to expand in a direction perpendicular to its longitudinal axis to form a tip portion, so that the tip portion has at least one surface (6, 7, 8, 9, 10, 11), which along at least a portion of the tip portion's length turns at least 35° in relation to a first plane in parallel with the longitudinal axis and at least 35° in relation to a plane at an angle in relation to the longitudinal axis.