Water pump pliers with a self-locking mechanism for pipes and screws, which prevents slipping from the workpiece and requires minimal hand pressure. The non-slip joint and plier profile are designed to fit screws and nuts. The joint design reduces stress on the central axis and prevents wear at the pivot point. The gripping surfaces feature specially hardened teeth with a hardness of approximately 61 HRC at a tool length of 250 mm, providing high abrasion resistance and a stable grip. The pliers have various capacities for half-moons, square, step-like square, triangular shapes, as well as spans for hexagonal, round, and square forms.