Do I Need an Amp Fuse for My Car and What Size? - Lifewire The reason that you should avoid connecting an amp to the fuse box inside your car, and especially never connect to an existing circuit or fuse, is that your amp is almost certainly going to draw more amperage than the wiring in your fuse box is designed to carry. Automotive Fuses - Walmart wwwart››Automotive ElectricalAutomotive Fuses. Showing 40 of 3024 results that match your query. Search Product Result. New 100pcs Auto Automotive Car Boat Truck Blade Fuse Box Assortment 2A 3A 5A 7 10A 15A 20A 25A 30A 35A Free Shipping. Heavy Duty Construction 4 or 8 Gauge Inline AGU Fuse Holder for Car Audio Amp. Product Image. Price $ 6. 25.