Aura Systems A2 Wireless Doorbell Set, Flashing Plugin and Vibrating Portable Receivers, Over 50 Chimes, 500 Meter Range, White Easy to Control: Interface allows you to select from over 50 tones with 4 adjustable levels of volume, ranging from 25db to 110db. Doorbell has an operating range of 500 feet (1,000 feet in open areas), perfect for households, offices, businesses, or even store fronts Functional Design: System comes with a portable and plugin receiver, specifically designed for assisted living, special needs, hearing impaired, deaf, or blind. Remote transmitter has capability of sending a wireless signal to both plugin and portable receiver Portable receiver has a vibrate function, making it perfect to use with included attachable belt clip in noisy environments Plugin receiver has LED flashing light and audio capabilities. 4 configurable modes include: only flashing, only music, flashing and music, or off Simple Installation: Transmitter can be wall mounted through double sided adhesive tape or crew and anchor hardware (recommended)