This page describes the Wrench for the IndustrialCraft2 Mod. You may be looking the Wrench from the BuildCraft3 Mod.
The Wrench (IndustrialCraft) is used to dismantle IC Machines and rotate the faces of energy storage devices such as BatBoxes, MFEs, MFSUs, and Transformers. To dismantle or change the output face of a machine, simply right click with the wrench. Press + "Right Click" to make the output face point away. It is required to dismantle most IndustrialCraft Machines