A luminaire head comprising: a thermally conductive metal body comprising a plate like portion , a tube portion and at least one cooling fin ; said plate like portion extending in a longitudinal direction (L) of the metal body and having a flat first surface and a second surface opposite said first surface, said tube portion extending in said longitudinal direction at said second surface, preferably extending substantially in the middle of the second surface of the plate like portion; said at least one cooling fin extending away from said second surface adjacent to the tube portion ; at least one support substrate with a plurality of light emitting elements , said at least one support substrate being arranged against the first surface, at least in an area opposite the tube portion; wherein the tube portion has a first open end which is closed by a removable closure , wherein the removable closure is a cap configured for closing off substantially fully the first open end; wherein at least one connector is attached to the removable closure ; wherein the removable closure comprises an attaching means configured for attaching at least one electrical or mechanical or optical component, such that the at least one electrical or mechanical or optical component is arranged within the tube portion ; wherein the tube portion is shaped to receive in a second open end thereof a rigid cylindrical end portion of a mounting base , such as a pole for the luminaire head; wherein the tube portion is provided with at least one hole for receiving a fixation means to fix the tube portion to the cylindrical end portion of the mounting base. a thermally conductive metal body comprising a plate like portion , a tube portion and at least one cooling fin ; said plate like portion extending in a longitudinal direction (L) of the metal body and having a flat first surface and a second surface opposite said first surface, said tube portion extending in said longitudinal direction at said second surface, preferably extending substantially in the middle of the second surface of the plate like portion; said at least one cooling fin extending away from said second surface adjacent to the tube portion ; said plate like portion extending in a longitudinal direction (L) of the metal body and having a flat first surface and a second surface opposite said first surface, said tube portion extending in said longitudinal direction at said second surface, preferably extending substantially in the middle of the second surface of the plate like portion; said at least one cooling fin extending away from said second surface adjacent to the tube portion ; at least one support substrate with a plurality of light emitting elements , said at least one support substrate being arranged against the first surface, at least in an area opposite the tube portion; wherein the tube portion has a first open end which is closed by a removable closure , wherein the removable closure is a cap configured for closing off substantially fully the first open end; wherein at least one connector is attached to the removable closure ; wherein the removable closure comprises an attaching means configured for attaching at least one electrical or mechanical or optical component, such that the at least one electrical or mechanical or optical component is arranged within the tube portion ; wherein the tube portion is shaped to receive in a second open end thereof a rigid cylindrical end portion of a mounting base , such as a pole for the luminaire head; wherein the tube portion is provided with at least one hole for receiving a fixation means to fix the tube portion to the cylindrical end portion of the mounting base. <EOS>