This multifunctional self-locking wrench uses a self-locking mechanism to fix the pipe, ensuring safety and stability when performing plumbing and heating repairs. Whether tightening or loosening, it can be easily dealt with. The self-locking wrench is designed for adjustment, which shortens the time spent on installation and adjustment. Users can complete tasks quickly and improve work efficiency, especially suitable for occasions that require frequent adjustments. The design of the self-locking wrench makes it suitable for a variety of pipe and fitting tasks in residential and industrial environments. Whether it is home pipe repair or industrial equipment maintenance, this wrench can meet different needs. The three-sided tooth design of the multifunctional adjustable pipe wrench can fix most types of fasteners, ensuring that they will not slip during use. This self-locking wrench can be used in daily environments. Whether it is hot, humid or other conditions, it can maintain good performance and ensure durability for daily use.