A socket assembly includes an outer socket, an inner socket mounted in the outer socket, and an intermediate socket mounted in the outer socket. The outer socket has a plurality of drive blocks and a plurality of retaining grooves. The inner socket includes a first base, a plurality of first driving sections, and a plurality of first openings. The intermediate socket includes a second base, a plurality of second driving sections, and a plurality of second openings. Thus, the inner diameter defined between the first driving sections is smaller than that defined between the second driving sections by 2 mm, and the inner diameter defined between the second driving sections is smaller than that defined between the drive blocks by 2 mm, so that the inner socket, the intermediate socket and the outer socket co-operate to operate three successive sizes of nuts.

A detachable and torque-adjustable cross wrench includes a primary bar and a torque-setting secondary bar, and an end of the primary bar is a socket insertion end and the other end of the primary bar is installed with an assistant turning handle provided for pivoting. A penetrating hole formed at a thickening middle section is provided for connecting the torque-setting secondary bar to form a cross wrench. The torque-setting secondary bar includes a plugging inner rod with a spacer ring slot, a force applying outer rod containing a torque-setting module, a handheld turning handle, an elastic pushing member, a torque-adjusting screw cap and a retaining ring. The torque-adjusting screw cap is provided for rotating and adjusting the torque-setting module to a predetermined torque value, so as to achieve an expected torque-setting.

A multi-purpose wrench tool includes a main wrench shaft member having one or two screwdriver heads and having a bore formed in the main wrench shaft member, and a rough member formed in the bore of the main wrench shaft member, and an elongated leverage bar includes a rough element formed on one end portion of the elongated leverage bar for engaging into the bore of the main wrench shaft member and for frictionally engaging with the rough member of the main wrench shaft member and for driving the main wrench shaft member with the elongated leverage bar. The elongated leverage bar includes an outer diameter (d) no greater than an inner diameter (D) of the bore of the main wrench shaft member.

A ratchet wrench structure includes a main body provided therein with a ratchet wheel, an actuating member and a restraining block positioned between the ratchet wheel and the actuating member. The restraining member has one side provided with two recessed portions, and the actuating member is provided with a position-limiting groove corresponding with the recessed portion, and an elastic member. When the actuating member is rotated, the elastic member will be actuated to push the recessed portion to have its front edge longitudinally and evenly pressing the recessed portion to enable the elastic member to support the restraining block in its entirety. Further, when the restraining block is stressed by rotation of the ratchet wheel, the restraining block can carry out reciprocating movement because of extension and contraction of the elastic member. Thus, the ratchet wrench structure can be simplified in number of components.