A well tool assembly comprising a setting tool and a plugging tool, where the setting tool comprises: - an inner actuator having a inner connection interface in its lower end; - an outer actuator having a outer connection interface in its lower end, where the setting tool is configured to provide relative axial motion between the inner and outer actuators (11, 16), thereby causing the plugging tool to be moved between its radially retracted state and its radially expanded state; where the plugging tool comprises: - an inner mandrel device having an inner connection interface connected to the inner connection interface of the setting tool; - an outer housing device provided radially outside of the mandrel device having a outer connection interface connected to the outer connection interface of the setting tool; - an upper sealing device comprising an upper sealing element provided axially between an upper section and a lower section; - a slips device comprising a slips element provided axially between an upper section and a lower section; - a lower sealing device comprising a sealing element provided axially between an upper section and a lower section; - a centralizing device comprising a centralizer element provided axially between an upper section and a lower section; where the upper sealing device, the slips device, the lower sealing device and the centralizing device are provided radially outside of the mandrel device; where the upper sealing device, the slips device, the lower sealing device and the centralizing device are connected to each other; where the centralizing device is provided below the lower sealing device or above the upper sealing device; characterized in that the slips device is provided axially between the upper and lower sealing devices (30, 50); where, when the centralizing device is provided below the lower sealing device: - the upper sealing device, the slips device, the lower sealing device and the upper section of the centralizing device are axially displaceable downwardly and upwardly in relation to the mandrel device; - the upper section of the upper sealing device is connected to the outer housing device and the lower section of the centralizing device is fixed to the inner mandrel device; or where, when the centralizing device is provided above the upper sealing device: - the centralizing device, the upper sealing device, the slips device and the upper section of the lower sealing device are axially displaceable downwardly and upwardly in relation to the mandrel device; - the upper section of the centralizing device is connected to the outer housing device and the lower section of the lower sealing device is fixed to the inner mandrel device. - an inner actuator having a inner connection interface in its lower end; - an outer actuator having a outer connection interface in its lower end, where the setting tool is configured to provide relative axial motion between the inner and outer actuators (11, 16), thereby causing the plugging tool to be moved between its radially retracted state and its radially expanded state; - an inner mandrel device having an inner connection interface connected to the inner connection interface of the setting tool; - an outer housing device provided radially outside of the mandrel device having a outer connection interface connected to the outer connection interface of the setting tool; - an upper sealing device comprising an upper sealing element provided axially between an upper section and a lower section; - a slips device comprising a slips element provided axially between an upper section and a lower section; - a lower sealing device comprising a sealing element provided axially between an upper section and a lower section; - a centralizing device comprising a centralizer element provided axially between an upper section and a lower section; - the upper sealing device, the slips device, the lower sealing device and the upper section of the centralizing device are axially displaceable downwardly and upwardly in relation to the mandrel device; - the upper section of the upper sealing device is connected to the outer housing device and the lower section of the centralizing device is fixed to the inner mandrel device; - the centralizing device, the upper sealing device, the slips device and the upper section of the lower sealing device are axially displaceable downwardly and upwardly in relation to the mandrel device; - the upper section of the centralizing device is connected to the outer housing device and the lower section of the lower sealing device is fixed to the inner mandrel device.