This product worked OK initially but then fell apart. I used it on the starter battery. The yellow plastic broke in less than a month. I came up with a way to reattach it used it for the rest of the season. Corrosion quickly took its toll and finally the engine wouldn't start due to fact that the starter wasn't getting enough power. I removed the switch and the engine now starts fine. My pricey alternator failed recently. I now believe that it was working to hard to overcome the resistance that this switch was producing. This switch now resides in the bottom of my trash can. Next time I'll spend the money for a better product.