PURPOSE: To surely switch a turn direction of a handle by separating arrow types of six protrusive legs on a circular annular unit from recessed parts of irregular teeth on a hexagonal axis flange disk by one-touch action such as only pressing an upper surface of a knob with the thumb of a hand gripping the handle.

CONSTITUTION: When a turn direction is desired to be changed of a handle, a knob 16 on a head part 2 is pressed by the thumb while gripping the handle. Then, since an elastic device 17 is contracted to press a hexagonal axis 11 integrally formed with the knob 16, an irregular teeth part 15 on a flange disk 14 is separated from arrow types 9 of upper protrusive legs 8 to release a meshing condition between both the teeth part and the arrow type. Now for instance, when desired to perform a left turn from a right turn, the knob 16 is first turned about 15° in a right direction without detaching the thumb from pressing the upper surface of the knob 16. Then, the arrow type 9 of the protrusive leg 8 is moved onto the adjacent recessed part. Simultaneously, a position of needle rollers 10 is moved from one angular part to the other angular part in each side surface of the hexagonal axis 11.