Hook Spanner is used to tighten, loosen, or retain round, notched, or multi-faceted machinery parts like lock nuts and pipe fittings. The inner side of a hook wrench's curve typically ends in a small, downward-pointing tooth or claw, regardless of whether the head or hook is fixed in place or movable. Hook Spanner is utilized to repair ring nuts of all sizes and shapes, including those with front holes. The usage of this spanner in particular is limited to the field of automobile and motorbike maintenance.