Abstract: A pair of plumbing pliers includes two levers, a pawl and a torque spring. After adjusting the desired bite size according to a diameter of a pipe, the levers are pivoted relative to each other in a first range to clamp and release the pipe repeatedly to rotate the pipe. To adjust a bite size of the pair of plumbing pliers according to a diameter of another pipe, the levers are pivoted and then moved relative to each other in a second range. Little resistance is encountered in the first range. However, considerable resistance is encountered in the second range. Hence, the difference between the first and second ranges can easily be felt. Accordingly, it is not likely that a user will, by mistake, enter the second range, i.e., increase the bite size of the pair of plumbing pliers.