150M/500Ft Wireless Range: Aigostar doorbell wireless has a reliable wireless range of 150M/500Ft and strong signal penetration. And the featured led flash indicators are friendly for the elderly and the hearing impaired. 36 Chimes 3 Volume Levels: This black and white battery doorbell featured a memory function. Well-made stereo speakers deliver 36 crisp chimes, the volume button to set with 3 volume levels which are also friendly to sleeping kids or the old. Waterproof doorbells’ Sensitive Transmitter: Extreme-low power consumption, included a 23A 12V alkaline battery that boasts a 3-year maximum lifespan. Dustproof and waterproof IP44 and the working temperature of this wireless doorbell ranges from -20-60℃. Easy to Install Wireless Door Bell: The doorbell is wireless, compared with a plug-in doorbell without the hassle of cables. Just hang the mini receiver into a hook or nail, and fix the transmitter (including battery) on a wall with the double tapes. 100% Risk-free Satisfaction - Each Aigostar cordless doorbell will be meticulously tested by our in-house engineering team to proactively address and prevent design or mechanical issues. If there are any problems, doubts or suggestions, please do not hesitate to contact us.