1byone Easy Chime Wireless Doorbell Kit, 2 Plug-in Receivers & 1 Push Button with CD Quality Sound and LED Flash 36 Melodies to Choose, Black Compact Design - Place this kits push button and receiver anywhere, and always be notified when a visitor arrives no matter where you are in the house 36 Selectable Ringtones - Choose from a variety of 36 different ringtones, with 3 levels of adjustable volume (High/Medium/Low) from 25-110dB 3 Notification Modes - Press the Sound-and-Flash Button to set your preferred notification mode. Modes include sound only, LED flash only, and sound and LED flash combined Easy Installation - The chiming receiver unit can be free standing or wall mounted using the included hardware. The wireless push button can be fixed to a doorframe with screws or using attached adhesive tapes. Waterproof push button effectively increases its security DIY Expandability - Expand this system to fit your needs by pairing up to 5 push buttons to your receiver. Each push button can also be paired with multiple receivers to increase the notification coverage area. Easily expandable to meet your requirements!