Waytek's new ATO and ATM (mini) fuses have an LED light that lights up when the fuse is blown, making for easy identification of blown fuses in hard to reach fuse panels. These fuses come in ATO and ATM styles and are color coded to let you know the right amperage of fuse to replace. This is great for circuits that have a history of blown fuses, as it makes it simple to replace, saving time and money.