There are literally hundreds of tools out there to close a spark plug gap. But what happens when your over-gap a plug and need to undo it? That's where this handy tool comes in: Our new Spark Plug UnGapping tool will let you safely and precisely expand the gaps of any massive electrode spark plug. To use it, simply insert the tool over the center electrode and press firmly with a slight twisting action to gently move the outer electrodes away from the center. Works with any type of massive electrode spark plug.