Features: Intercom doorphone for double rooms, two hundred talk distance, more convenient. Operation distance 200m, 2-line connected, strong signal and clear communication. Easy to install, DIY installation, can be placed on the desktop or hanging walls. Energy saving and no current consumption while not work. Practical and convenient, widely used in offices, warehouses, families, etc. Specifications: Color: White Battery: 1.5V (each unit need 4pcs AA batteries, the batteries are not included) Working Currency: <100mA Bell Rings Grade:>70DB(0.5 meter distance) Connection: by wire RVV2 (the cable is not included for this listing) Material: ABS Size: Approx. 22.2 x 8.7 x 7.3cm/8.7 x 3.4 x 2.9in Package Weight: 752g/26.5oz Package List: 2 x Intercom Doorphone( Batteries are not included) . Note: When using, you need to connect the radios of the same color (within a range of 50 meters, it is best to use RVV2*0.5mm line, and within 100 meters, it is best to use RVV2*1.0mm line)