The REDARC 40A Fuse Kit is equipped with high-quality fuses and fuse holders to fit the cable required for the specified current and make a solid connection. This ensures your installation is working safely and efficiently. Poor quality fuse holders typically don't make enough contact with the fuse, which allows dirt and other elements to get in between contact points. This generates excess heat, which can be enough to melt both the fuse and the holder.. . . . .