Many of the lighting devices on motor vehicles are required and essential to operation on public roadways. To assure field replacement, it is important that the bulb types employed be readily available, when needed, in normal service channels. Therefore, this document lists an assortment of current popular types, together with their design characteristics, which are recommended for use wherever practicable. It is recognized that because of constantly changing and improving technology, the list may be incomplete. Also, instances may arise in the design of some devices that require the employment of other types while achieving the desired performance. Some of the design characteristics in this document are listed solely for the sake of standardization and have no bearing on how lamp bulbs perform in lighting devices on the highway.