Condition: 100% Brand New Item Type: Wireless Intercom Doorbell Material: ABS Plastic Optional Color: White+Gold, Black+Gold Outdoor Unit Working Voltage: 3 x AA alkaline battery (3 x 1.5V) (not included) Working Temperature: -20-55℃ Transmission Distance: Approx. 200m / 656.2ft (without any obstacle), obstacles 50 - 100m / 164 - 328.1ft Working Frequency: 467MHZ Working Time: More than four months Indoor Unit Working Voltage: Rechargeable Li-Ion Battery (Built-in) Working Temperature: -20-55℃ Transmission Distance: Approx. 300m / 984.3ft (without any obstacle), obstacles 50 - 100m / 164 - 328.1ft Wireless Frequency: 467.6375MHZ 1、This wireless voice doorbell talk with visitor via two-way voice intercom, know who visit your home, speak to them and let them know I'm coming, please wait. 2、Low power consumption, long standby time for outdoor?bell up to four months. 3、Outdoor-bell is power supplied by 3pcs alkaline battery, easy to replace the battery, indoor-bell is power supplied by rechargeable Li-ion battery. 4、Big and adjustable speaker, clear voice, can be used as mobile interphone. 5、Strong and stable signal transmission in big house, cover range up to 200m / 656.2ft (without any obstacle, any block). It is super convenient to answer the doorbell of the visitor at any distance in your room. 6、Easy to install, the doorbell can be attached to the wall using the included sticker. 7、It has 15 ringing tones to choose from, and 3-speed volume can be adjusted to 120dB. 1 x Indoor Intercom 1 x Outdoor Intercom 1 x USB Interface Cable 1 x Screwdriver 1 x User Manual 2 x Sticker