This MAX fuse is rated for 40 amps. MAXI or MAX fuses are fast-acting blade fuses used in cars, trucks, vans, and other vehicles to protect circuits in the wiring harness. You'll usually find these fuses used under the hood of the vehicle but they may be found in the main fuse panel or supplementary panel as well. These fuses are an excellent choice to protect after market accessories such as high-end stereo amplifiers, speakers, and other equipment that requires protection up to 80 amps.