The Pure Sounds Digital Audio Monitor by MobiCam compact design makes it easy to carry within a wide, 600 foot area. You will hear your little ones with clarity and in complete security. Pure Sounds technology allows the sound signals to penetrate walls and travel through floors and ceilings. With its built-in rechargeable battery for the monitor, the Pure Sounds Wireless Audio Monitor is environmentally friendly - designed for high performance and peace of mind for today's families.