1. Long-distance intercom: Barrier-free long-distance call distance supports about 1000 meters, no network or wiring required, easy to use. 2. Long standby: Built-in 2000mAh battery, long battery life, press 5 times a day, call for 2 minutes, can work for about 8 months, indoor unit works for about 1 week. 3. Humanized: Humanized design, equipped with intercom indicator light and power lamp display, convenient surface pattern for quick communication. 4. Button design: The button adopts plastic and silicone structure, the surface adopts high-gloss UV process, 18mm thickness is convenient and comfortable to hold. 5. Convenient: When the indoor unit rings, press the TALK button to intercom directly, equipped with a charging station, and it can be fully charged in five hours. Specification: Item Type: Wireless Intercom Ringtones Material: ABS Door machine: 2000 mAh 103450 polymer lithium battery (built-in). Indoor unit: 2000mAh 103450 polymer lithium battery (built-in) Operating temperature: -20-55 Transmission distance: About 1000 meters no-load Working frequency: B speed frequency 462MHz, A speed frequency 434MHz Working time Charging: About 5 hours for full charge Music Ringtones: Optional Ringtone volume: 3 gear adjustment (sleep to adjust volume key) Call sound: 3 gear adjustment (working time adjustment volume keys call) Package List: 1 Transmitter 1 Receiver 1 x Charging Cradle 1 x Charging Cable 1 Screwdriver 1 Instruction Manual. 1 x double-sided adhesive 1 x adapter cable