Maximum capability wrench

A hand held multi-torque wrench comprising an elongated housing, toothed jaw means mounted within said housing adjacent one end thereof floating rotationally, said end of said housing having a jaw opening for permitting access to said jaw means, a pair of spaced pinions within said housing for engaging the toothed elements of said jaw means, a pair of gears engaging said pinions, respectively, drive pinion means engaged to drive both of said gears, a chain driven element connected to rotate with said drive pinion means, external driving means within said housing adjacent the other end thereof, overruning clutch means within said driving means to permit ratchet operation of the latter upon being rotated by an external source of power with said housing stationary, and a chain drive between said driving means and said chain driven element, said hand held wrench being selectively operable as a wrench by rotating said housing or for torque multiplication with said housing stationary and rotational force applied to said driving means, said driving means including a toothed member having a power take-off extension, said toothed member containing said overrunning clutch means, the toothed elements of said toothed member engaging said chain drive, said power take-off extension terminating within said housing, said open jaw means being comprised of central and outer sections, said central section carrying the toothed elements and said outer sections having a diameter less than that of said central section, and insert means for fitting into the jaw opening of said jaw means to accomodate nuts of smaller size, each of said insert means being slotted for mating with the central and side sections of said jaw means.