Abstract: An adjustable wrench for use in rotating screw-on oil filters and the like. The wrench has a strap for encircling the filter, and a lever for tightening the strap about the filter. The lever has a first end attached to a first end of the strap, an intermediate portion attached to the second end of the strap, and a second end for movement between a first position in which the strap is loose about the filter and a second position in which the strap is tight about the filter. The second end of the lever being located substantially at the center of a circle defined by the strap when in the second position.