This small, lightweight, omnidirectional microphone is pinned under an actor's clothing or taped to the body. It must be carefully placed so as not to pick up
Lavalieres are effective microphones if the actor remains fairly stationary during a take, but if the actor is required to walk, dragging the microphone cable might be awkward. A radio microphone might be needed in this case.
Lavalieres are often used when interviewing subjects for documentaries.