Open-end wrench

In an open-end wrench of the type wherein an elongate handle terminates at either end in jaws forming a U-shaped recess to receive a nut, the improvement comprising:

• groove means formed on the inside of said U-shaped recess, resilient insert means positioned within said groove means so as to protrude into said U-shaped recess, said resilient insert means being formed as a substantially U-shaped length of spring wire having an inner loop portion which entirely protrudes into said U-shaped recess and opposed shank portions which partially protrude into said U-shaped recess, such positioning of the spring wire within said groove means facilitating initial grasping and retention of a nut between said shank portions and subsequent inward locking movements of said spring wire with respect to both said groove means and said U-shaped recess in response to contact of the nut with said loop portion, said substantially U-shaped length of spring wire being additionally provided with outwardly flaring tip portions on said shank portions which protrude slightly beyond open ends of the groove means within said U-shaped recess, the diameter of said spring wire being slightly greater than the depth of said groove means so that outward expansion of said spring wire can be only partially accommodated within said groove means whereby a nut can be slidingly engaged within said U-shaped recess between said shank portions of the spring wire and thereafter with the loop portion of said spring wire to cause said outwardly flaring tip portions of the spring wire to slidably engage within said groove means to lock both the nut and the spring wire in place by compression.