Abstract: A hex wrench includes a main body, a handle connected with the main body, a rotary member, a lifting member, a driving member, and a matching member. The rotary member includes an operation portion and a shaft portion. The driving member includes six host driving members and six guest driving members. The matching member includes six matching blocks. The shaft portion passes through the main body. One end of the shaft portion is connected to the operation portion, the other opposite end is connected to the lifting member. One end of each host driving member is rotatably connected with the lifting member, the other end is rotatably connected with a middle portion of a corresponding guest driving member. One end of each guest driving member is rotatably connected with the main body, the other end is rotatably connected to a corresponding matching block.

Abstract: A mounting and dismounting device for cylindrical bodies comprises a fixing element, a moving element, and a buckling element. The fixing element connects to the moving element on both sides to form a hole. The cylindrical body is then inserted into the hole. A buckling part of the buckling element pivotally connects to the fixing element. One lifts a lifting part for the buckling element to urge against the cylindrical body in the hole. By lifting the lifting part, the cylindrical body can be mounted or dismounted.

Abstract: A manually or mechanically/hydraulically operable tong of light weight and high load capacity by means of a multi-layer interlocking construction achieved by cutting the shapes from plate steel by known means, assembling the plate sections in suitable order, and retained with each other by cylindrical steel pins (8) forming a multi hinged tool capable of engaging the job circumference on two or more points equally via replaceable jaw dies (15) retained radially and axially.

Abstract: A wrench has a head portion (10) adapted to engage and apply torque to a workpiece, including a ring member (14) which surrounds the workpiece and has a fixed end (16) and a free end (18) such that, when the ring engages a workpiece and a torque is applied in a predetermined direction (48), the ring closes around the workpiece, increasing the grip between the wrench and the workpiece even if the workpiece is substantially worn, damaged or undersized.