PURPOSE: To change a handle suitable for operators by providing a power transmission device separately from a pistol type handle.

CONSTITUTION: This hand held power tool comprises a housing 10, a motor 14, a pistol type handle 12 vertically extended from the housing 10 to the application direction of the tool, and a power communication means 16, 20, 23 including a power supply controlling means 20 for controlling the motive power supply from a power supply conduit to the motor 14. The power communication means 16, 20, 23 inclusive of the power supply controlling means 20 is separated from the handle 12. The pistol type handle 12 comprises a trigger 22 for operating the power supply controlling means 20 and a detachable grip member 28 which is selected as an optimum one from a set of many interchangeable grip elements of different sizes and/or shapes to fit individual operators.