Operating Temperature: 55°C Transmission Distance: Approximately 1,000m/3,280ft in open space, 20 to 100m/66 to 328ft with walls, adjustable from level 1 to 8 Working Frequency: Switch B frequency 462MHz, Switch A frequency 434MHz Battery Life: Approximately 8 months, with the indoor unit requiring charging once every 3 days Charging Time: Approximately 5 hours for a full charge Musical Ringtones: 38 ringtones to choose from Ringtone Volume: 3-level adjustable volume (machine standby volume setting) Call Volume: 3-level adjustable call volume (volume adjustment button during calls) Outdoor Unit Waterproof Rating: IP54 Indoor Unit Waterproof Rating: No Battery Capacity: 3.7V/1800mAh Available Colors: White, Black (optional) Product Options: 1 outdoor unit with 1 indoor unit, 1 outdoor unit with 2 indoor units (optional) Outdoor and Indoor Unit Size: 116 x 56 x 18mm/4.6 x 2.2 x 0.8in Waterproof Cover Size: 121.5 x 61.5 x 31.3mm/4.8 x 2.4 x 1.3in Charging Station Size: 70 x 56 x 29mm/2.8 x 2.2 x 1.1in Important Notes: 1. After the outdoor unit calls the indoor unit, and the indoor unit presses PTT to hang up, the outdoor unit will stop ringing after 30 seconds. 2. If the outdoor unit calls the indoor unit and there is no response or ringtone, the channel needs to be re-established. 3. When both indoor and outdoor units are off, press and hold the PTT button on the indoor unit. The outdoor unit will operate synchronously. Release the PTT button when the indoor unit displays a white flash to complete the pairing. Please Note: Due to different monitor and light effects, the actual color of the item might be slightly different from the color shown in the pictures. Package Includes: 1 * Outdoor Unit 1 * Indoor Unit 1 * Instruction Manual 1 * Charging Cable 1 * Wall Mount