The 3057 and 3157 are long-life bulbs that are commonly used in vehicle tail lights. The type of light differs mostly in size and brightness and is interchangeable in most vehicles. The bulbs come in different colours and can even be purchased as a light-emitting diode or LED light bulb.
The 3057 bulb is a miniature bulb with a wedge base made from plastic. It produces 12.8/14.0 volts and 2.1/0.48 amps. It is 2.09 inches long and is expected to last about 1,200 to 5,000 average-rated hours. The 3057 bulb can be used in automobiles, aircraft, instruments, marine and railroad equipment.
The 3157 bulb produces 12.8/14 volts and 2.1/05.93 amps. The filament is C6 and it lasts from 2,000 to 10,000 average-rated hours. The 3157 is 1.25 inches long and is commonly used in automobiles.
The major difference between the 3057 and the 3157 is the brightness of the filament. The filament is the metal wire that is heated inside the bulb or lamp. The filament in the 3157 is able to glow brighter than that of the 3057. Some automobile taillights and other lamp bulbs may be fitted with one or the other type of bulb; however, many sockets may be interchangeable.
The other major difference is that the 3157 lasts for more average-rated hours than the 3057. However, this will depend on the user and how often the bulb is in use. The other difference is in the size of the bulb; the 3057 is larger.