A wrench head comprises a working axis, a first jaw, a second jaw, and a third jaw. The first jaw comprises first-jaw arcuate convex contact surfaces. The second jaw is coupled with and pivotable relative to the first jaw and comprises a second-jaw arcuate convex contact surface and a second-jaw planar contact surface. The third jaw is coupled with and pivotable relative to the second jaw and comprises a third-jaw arcuate convex contact surface and a third-jaw planar contact surface.

A wrench head comprises a working axis, a first jaw, a second jaw, and a third jaw. The first jaw comprises a first-jaw arcuate convex contact surface, a second first-jaw arcuate convex contact surface, a third first-jaw arcuate convex contact surface, and a first-jaw planar contact surface. The second jaw is coupled with and pivotable relative to the first jaw and comprises a second-jaw arcuate convex contact surface, a second second-jaw arcuate convex contact surface, and a second-jaw planar contact surface. The third jaw is coupled with and pivotable relative to the second jaw and comprises a third-jaw arcuate convex contact surface and a third-jaw planar contact surface.

A removable stud, tool for inserting and removing the stud and kits comprising the studs and tool are provided. The removable stud comprises a hexagonal head portion connected to a threaded pointed shank portion. The hexagonal head portion includes a notched flange portion that has two diametrically opposed notches that are each centered on a vertex of the hexagonal head. The tool includes a wrench head comprising a neck with two substantially diametrically opposed walls extended therefrom. Each wall has an interior face configured to receive a vertex of the hexagonal head of the stud and a tip portion configured for the notch of the stud.

A removable stud, tool for inserting and removing the stud and kits comprising the studs and tool are provided. The removable stud comprises a hexagonal head portion connected to a threaded pointed shank portion. The hexagonal head portion includes a notched flange portion that has two diametrically opposed notches that are each centered on a vertex of the hexagonal head. The tool includes a wrench head comprising a neck with two substantially diametrically opposed walls extended therefrom. Each wall has an interior face configured to receive a vertex of the hexagonal head of the stud and a tip portion configured for the notch of the stud.

A torque wrench includes a first part, a second part, a first spring, a block and a second spring. The first part includes a first section and a second. An axial passage is defined through the first part and a second part is received in the passage. The first part and the second part are connected to each other. The first spring is securely located in the second section. A pushing member is located in the first spring and includes a second contact portion. The block is removably in contact between the first and second contact portions. A second spring is mounted to the pushing member. The block is disengaged from the first and second contact portions when the torque wrench rotates clockwise or counter clockwise.

A wrench head comprises a working axis, a first jaw, a second jaw, and a third jaw. The first jaw comprises first-jaw arcuate convex contact surfaces. The second jaw is coupled with and pivotable relative to the first jaw and comprises a second-jaw arcuate convex contact surface, a second second-jaw arcuate convex contact surface, and a second-jaw planar contact surface. The third jaw is coupled with and pivotable relative to the second jaw and comprises a third-jaw arcuate convex contact surface and a third-jaw planar contact surface.

A wrench head comprises a working axis, a first jaw, a second jaw, and a third jaw. The first jaw comprises a first-jaw arcuate convex contact surface, a second first-jaw arcuate convex contact surface, a third first-jaw arcuate convex contact surface, and a first-jaw planar contact surface. The second jaw is coupled with and pivotable relative to the first jaw and comprises a second-jaw arcuate convex contact surface and a second-jaw planar contact surface. The third jaw is coupled with and pivotable relative to the second jaw and comprises third-jaw arcuate convex contact surfaces.

The invention provides a multiple use open-end wrench with an elongate handle having a proximal end, an opposing distal end and a longitudinal axis extending therebetween, and a first wrenching head arranged at the proximal end of the elongated handle formed with an opening for receiving and turning a plurality of varying sized fasteners. The opening is formed by opposing left and right jaws with opposing parallel left and right jaw surfaces, the opening having a fixed length L in the aggregate that extends from an end tip of the proximal end substantially in parallel with the opposing parallel jaw surfaces.

The invention provides a multiple use open-end wrench with an elongate handle having a proximal end, an opposing distal end and a longitudinal axis extending therebetween, and a first wrenching head arranged at the proximal end of the elongated handle formed with an opening for receiving and turning a plurality of varying sized fasteners. The opening is formed by opposing left and right jaws with opposing parallel left and right jaw surfaces, the opening having a fixed length L in the aggregate that extends from an end tip of the proximal end substantially in parallel with the opposing parallel jaw surfaces.

A screwing device for applying and/or transmitting a torque to a screw partner and for interacting with a drive torque generating means, including flat output means (6) which have an output that, can be detachably connected to the screw partner and a drive, to which a drive torque can be manually or mechanically applied, an output gearwheel (8) that can be driven by the fiat output means (6), a mechanical interface (46) for selective direct or indirect connection to the drive torque generating means for initiating the torque, a compensation unit (30) which is designed to store and process compensation data and which comprises an output gearwheel-specific torque curve and/or an output gearwheel-specific efficiency curve for calculating it with a value of an actual output torque in order to generate a value of a compensated output torque, and a data interface (36) which is designed to transmit compensation data to a drive torque generating means.