Manually operated tool e.g. screw wrench has main body with assembly element with protruding faces and indentations with specific ratio of depth of protrusion to distance between edges of indentations

摘要

The tool comprises a main body (10) with assembly element (22) with several protruding faces (24) and several indentations (23). The ratio of the depth of each protruding face and the distance between the edge (25) of each indentation and the edge of each adjoining indentation corresponds to 1 to 1.6. Each indentation has a curved edge with small radius.