Means for adjusting cutting height of a powered lawn mower

A lawn mower cutter unit comprising a cutter propulsion unit with a transmission axle that is adapted to be rotated around a common rotation axis, a hub that is rotatably connected to the transmission axle, a cutting disc, and a knob that is rotatably connected to the hub such that the knob is adapted to rotate with the hub and the transmission axle, wherein the cutting disc is displaceable along the common rotation axis, against a spring force of a spring element, wherein the cutting disc and the knob are comprised in a coupling interface that is comprised in the lawn mower cutter unit and adapted to transfer a rotational torque transferred from the hub to the cutting disc, the coupling interface being adapted to releasably lock the cutting disc in mutually separated positions along the common rotation axis via the spring force, conferring an associated certain grass cutting height for each locked position,

• wherein the cutting disc comprises a connection portion that comprises an aperture and at least two engagement recesses which are formed in the aperture and extend to at last two mutually different depths parallel to the common rotation axis, and wherein the knob comprises a coupling protrusion that extends away from the common rotation axis and is adapted to transfer a rotational torque transferred from the hub to the cutting disc via a corresponding one of the at least two engagement recesses, the at least two engagement recesses being adapted to receive said coupling protrusion in at least two different mounting positions along the common rotation axis, wherein the mounting positions are locked by means of the spring force such that the cutting disc obtains a certain vertical position along the common rotation axis in dependence of which of the at least two engagement recesses has received the corresponding coupling protrusion.