A head part (11) for a multi-chamber tube bag (1) with a multi-component mass which can be pressed out, having a main chamber (2) for a first component and two secondary chambers (3, 4) for two other components, has a disk-shaped contact surface (12) for the multi-chamber tube bag (1) surrounding a press-out opening (13). At the contact surface (12), a plurality of raised portions (14) project toward the multi-chamber tube bag (1) and are provided at the head part (11) for narrowing the outlet regions (5, 6) of the two secondary chambers (3, 4) of the multi-chamber tube bag (1) when the multi-chamber tube bag (1) bears against the contact surface (12).