Wireless doorbell intercom 180-A shell

Features：Doorbell intercom. 1. Wireless transmission of voice can be used as a doorbell and intercom. 2. Can write frequency change frequency Special writing frequency software Special writing frequency line. 3. The sound is loud and clear. 4. It can communicate with multiple internal machines. 5. You can choose multiple voices, up to 10 voices. 6. The transmit power is 1W. 7. A set of external machine, internal machine, rain cover and seat charger. 8. Suitable for factories, communities, houses, office buildings and offices. 9. The internal machine and the internal machine can talk directly, and a large number of people can hear it. 10. Use in mining areas, schools, stations, and other places.