General description The Discipline Wireless Doorbell Calling Device is a smart doorbell designed for home reminders and two-way calls. Its slim profile, measuring only 18mm in thickness, offers a sleek and modern look compared to other bulkier models on the market. This device features a user-friendly interface with high-quality materials for a comfortable feel. Technical specifications Power supply mode: Rechargeable lithium batteries for both outdoor and indoor units Battery capacity: 2000mAh for both units Working temperature: -20°C to 55°C Transmission distance: Approximately 1000 meters in open space Working frequency: B frequency 462 MHz, A frequency 434 MHz Charging time: About 5 hours Host size: Outdoor and indoor unit dimensions: 116 x 56 x 18 mm Waterproof cover size: 121.5 x 61.5 x 31.3 mm Charging base size: 70 x 56 x 29 mm Ring volume: 3 levels of adjustment Call sound: 3 levels of adjustment Compatibility and accessories Includes two indoor units Optional music ringtone