1、[Wireless Intercom System] This doorbell intercom kit includes three units, two indoor and one outdoor, allowing for switching between ringtone call and intercom mode. 2、[Indicator Lights] Humanized design with intercom and power indicator lights, this wireless intercom doorbell provides clear visual cues for users. 3、[Long Range] The transfer distance of this intercom system can achieve up to 1000 meters in open area, and 20 to 50 meters through wall, offering strong practicality. 4、[Adjustable Function] Portable intercom system with 2 channels A and B, and 3 volume levels, allowing users to customize settings according to their preferences. 5、[Wide Applications] This clear sound intercom system is suitable for various scenarios such as hospitals, hotels, factories, and teahouses. Item Type: Wireless Intercom Doorbell Material: ABS Waterproof Rating: IP54 Battery: Indoor Unit: Rechargeable lithium battery 3.7V 1800mAh (built in) Outdoor Unit: Rechargeable lithium battery 3.7V 1800mAh (built in) Use: Widely used in household, office, laboratory environment, medicine facility, etc. Basic Parameters: Working Temperature: -20℃ to 55℃ Transfer Distance: Open Field: 1000m Through Wall: 20-50m Operating Frequency: 410MHz to 490MHz 2 x Indoor Units 1 x Outdoor Unit 2 x Bases 2 x Data Cables 1 x DC Power Cord 1 x User Manual 1 x Sticker 1 x Screwdriver