Microphones.

These are often the same as the microphones used with some CBs and are intended to replace the original microphone if they break. There are different shapes available, but they mostly work basically the same and offer no improvement over the original.

There are three main types of standard microphone, depending on the actual element type used inside.
 - DYNAMIC: By far, the most common. These are like a miniature speaker and so use magnets.
 - ELECTRET. Less commonly used as standard on CBs, but some Midland type radios have been known to use them. There is a small compatibility issue with these microphones: an electret microphone will only work on a radio designed to run one and will not work on some microphone testers, but a radio which uses one of these can also work with a dynamic type microphone.
 - Crystal. Not used as standard on UK CBs, but some crystal replacement microphones have been seen. As UK CBs are designed to run with a dynamic microphone, these may not sound as good on UK CBs.