FiBiSonic Portable Wireless Door Bell Chime and Push Button with Batteries Included Range up to 350 Feet for Tabletop Use or Wall Mounting, Blue 3 signal options: acoustic, visual, acoustic + visual; 16 ring tones and 4 volume settings Range up to 500 feet at open area, and averagely home use is 350 feet. Receiver(doorbell) for tabletop use or wall mounting(assembly materials included); splashproof transmitter(push button) as per IP 44. If you need more doorbells, the doorbell can also meet your needs. Because one receiver(doorbell) can match with at most 5 transmitters(push buttons), and one transmitter(push button) can match with multiple receivers(doorbells). The package includes: 1 transmitter(push button); 1 receiver(doorbell)(size of the door bell: 175mm*115mm*35mm); 3 batteries 1.5V (type AA for receiver); 1 battery 3V (type CR2032 for transmitter); 3 screws(for transmitter and for mounting the receiver on a wall); 3 dowels; 5 name plates(for the doorbell); 1 operating instruction.