There are at least eight or more different styles or sizes of fuses found in cars today. Most fuses found in newer vehicles are blade-style fuses, which are thin and U-shaped, with colored, plastic spines and two or three prongs that resemble electrical plugs.
There are six different sizes of blade type fuses: micro2, micro3, mini, low-profile mini, regular and maxi. These fuses use a standardized color-coding system to indicate their amperage handling capacity and have ratings that range from 0.5 up to 130 amps. They generally control items found in the vehicle's interior, such as the fuel gauge or radio, or outside components such as directional signals and brake lights.
There are also larger square and rectangular-shaped fuses that resemble cubes or blocks with prongs that plug into fuse sockets. Some have round screws that bolt into a fuse holder and have amperage ratings from 35 to 750 amps. These control components with more demanding electrical requirements such as air conditioners, or serve as relay switches for automatic transmissions.
Cylindrical or AG and AGU fuses resemble narrow glass tubes with metal caps on each end. Older vehicles and some overhead interior lights generally use these fuses. They may have a rating from 30 up to 65 amps, which is etched on the metal caps, and normally have one or two sizes.