A battery operated handheld power tool, the power tool (1) comprising a working tool assembly (20), comprising a working tool of the power tool and an electric motor, arranged to drive the working tool, a handle assembly (10), comprising a body portion (11) to which a battery pack (13) may be detachably connected, which battery pack (13) is arranged to provide electric power to the electric motor, a control unit (15), provided in the body portion (16) so as to control a flow of electric current from the battery pack (13) to the motor. The battery operated handheld power tool is characterized in that the body portion (11) comprises a fan (14), arranged to generate a flow of air passing by the control unit (15) during operation of the power tool (1).
