This product is a 10A/15A/20A/30A inline fuse embedded into a waterproof fuse holder. It features an solar connector lead on each end, making it compatible for use with an Adaptor Kit and solar panel leads. This Fuse Holder is designed to provide complete single circuit protection to your solar power array. The fuses prevent large currents from damaging the solar panels. Purchase this product for extra protection on your system.