The PowerPen™ battery saver is the only way to clean batteries and conductive terminals. Non-toxic and non-corrosive the PowerPen™ contains an all natural cleaner which leaves a slight residue but does not impede conductivity. To the contrary it removes oxidation. And the residue left behind keeps the battery or contact from oxidizing which lowers contact resistance thereby giving the battery longer life. The fine tip makes it great to use on all types of watch batteries. Good for 50-75 applications PowerPen™ can be used on all batteries except zinc air batteries.