These bulbs are small, but very bright, so they're often used in flashlights and optical instruments such as projectors and microscopes.

Bulbs have two filaments, which operate at different brightness levels.

Bulbs have two filaments, which operate at different brightness levels.

These miniature bulbs are sized to fit older telephone switchboards, signs, instruments, and indicators.

Often used as status indicators, in displays, or to check circuit function in prototyping and testing, these bulbs have wire terminals to directly install onto circuit boards.

Offset pins on the base lock these bulbs into sockets. One pin is slightly higher on the base than the other pin.