Ratchet wrench

A ratchet wrench comprising:

• a body having a head and a handle connected to the head, wherein the body is provided with a through-hole at the head in a height direction, wherein on an inner periphery of the through-hole is formed a first annular slot;
• and
• a ratchet wheel rotatably disposed in the head and having a first diameter portion, a second diameter portion connected to the first diameter portion, and a driving portion adapted to connect an object, wherein the first diameter portion defines a first diameter in a radial direction of the ratchet wheel, and wherein the second diameter portion defines a second diameter less than the first diameter in the radial direction of the ratchet wheel,
• wherein on an outer periphery of the second diameter portion is formed a second annular slot faced to the first annular slot, wherein a retainer is engaged in the first and second annular slots, wherein on the outer periphery of the second diameter portion is formed a ratchet teeth portion, wherein the ratchet wheel has a third diameter portion disposed between the second annular slot and the ratchet teeth portion, wherein the third diameter portion defines a third diameter less than the second diameter in the radial direction of the ratchet wheel, wherein the ratchet wheel further has a fourth diameter portion connected to the second diameter portion, wherein the fourth diameter portion defines a fourth diameter less than the third diameter in the radial direction of the ratchet wheel, and
• wherein the ratchet teeth portion is located adjacent between the third diameter portion and the fourth diameter portion.