Plug Fuse Box Cover Units - Fuse Accessories - Grainger 4 in. square fuse box cover units are easily installed in standard electric boxes to protect small motors in HVAC applications. Use with Bussmann® T, TL, TC, P, or W plug fuses. Brands Fuse Box Covers - CARiD Fuse Box Cover (W0133-1627374-APA) by URO Parts®. This superior electrical part by URO is a great alternative solution to the costly factory equipment that will help you restore smooth and efficient operation of your vehicle. Thoroughly..