Ultrasonic Bird Repeller By Birdgard India Pvt. Ltd.

A Device to Repel Pigeons and Birds in a Silent Manner
The Ultrasonic Pigeon Repeller is an "all in one" repeller, which includes all electronics and four independent speakers each with a 30 meter cable to give you added flexibility in positioning. The device uses digitalized recordings of Ultrasonic distress, predator and harassment sounds that are effective on Pigeons and other birds. Ultrason targets birds with unrelenting ultrasonic waves which move from speaker to speaker, delivering a constant, menacing multi-bird defense. Harmless to birds and the environment! The Ultrasonic sounds make the birds get a feeling akin to being sea sick and makes them uncomfortable forcing them to leave the area.
An added feature is the capacity to plug in one 360 degree multi-directional speaker with 30 m of cable so the actual sound can be projected from another spot remote from the actual control unit