Bussmann JCK-A Series medium voltage fuses are designed for retrofitting existing hardware, making them an ideal choice for upgrading electrical systems. These UL-listed fuses feature an open fuse indicator for easy troubleshooting, as they provide a visual indication when a fuse has blown. They come with an option of including a Cutler Hammer hook-eye, which simplifies the process of inserting and removing the fuses. These backup fuses offer reliable current-limited protection for medium-voltage motor controllers, ensuring the safety and smooth operation of the electrical system.