Wireless voice doorbell, can talk to visitors through two-way voice intercom, knowing the visitor, safer and more convenient than ordinary doorbell, especially suitable for the elderly at home Wireless doorbell, wireless connection between the indoor receiver and the doorbell. outdoor transmitter (maximum 600 feet) (the device will generate noise between 6.6 feet) Wireless doorbell, suitable for home battery power supply, the receiver supports rechargeable batteries, which can be used up to 24 hours after being fully charged (the receiver needs to be charged every day, and the receiver can be charged by putting the receiver in the charging base), the transmitter supports 3 * AA batteries, the battery can last for 2 months Wireless intercom doorbell suitable for home and office. Search "Napok H7A Doorbell" on YouTube for video instruction H7A wireless voice doorbell with two-way voice intercom function, let you know who is visiting your house, not just know someone is visiting your house, the visitor presses On the button of the transmitter, you can press the button of the receiver to talk to the visitor Talk, an updated version of the doorbell with basic wireless functions. The receiver can be moved with rechargeable batteries, can be carried around the kitchen, bedroom and living room, and can also be used in the office. Receive a reminder when the visitor presses the button on the receiver. A charging base has been updated so that the receiver can be charged. The receiver update function also supports intercom between receivers. A receiver and transmitter can operate at heights over 600 feet, enough to accommodate homes and offices. Easy to install and pair, enough accessories are provided in the package for installation. Built-in rechargeable battery for the receiver, working time: 24 hours after fully charged (needs to be charged every day). The transmitter's AAA battery can work for up to 2 months. Can't be waterproof, please protect it from rain and snow. Search "Napok H7A Doorbell" on YouTube for Video Instruction Specification Recipient: Power Supply: Li-ion rechargeable battery Working Hours: 24 hours after fully charged (need to be charged daily) Wireless Frequency: 467.6375mhz Temperature working: -20+55 Launcher: Power supply: 3 AA batteries (not included) Working time: 2 months Wireless frequency: 467.6375mhz Working temperature: -20~+55