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 spanner includes an upper jaw, a handle, a lower jaw, and a resilient member. The upper jaw includes an upper jaw portion, and a pivot portion, and has a front pivot hole and a rear pivot hole both of which extend through the pivot portion. The handle has a connection end extending into the pivot portion and pivoted to the upper jaw at the rear pivot hole. The lower jaw has a lower jaw portion, a tail portion, and an insert part projecting into the pivot portion of the upper jaw. The insert part is pivoted to the upper jaw at the front pivot hole. The resilient member is disposed between the tail portion and the connection end to bias the tail portion away from the connection end so that the lower jaw portion is biased toward the upper jaw portion.

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.

Abstract: A combination wrench with adjustable heads is provided. The wrench includes a handle and a open head and box head respectively pivoted to two ends of the handle. The open head is combined with a first and a second clamping jaws in shear arrangement. The box head is combined with a first and a second web pivoted together at their distal portions. When rotate the handle counterclockwise, both the open head and the box head can be able to firmly comp a wording object and then to fasten or unfasten the object. The handle can make back runs when it rotates clockwise.