AUTOMATIC POWER - This wireless doorbell requires no batteries or external power! By simply pressing the button, it converts kinetic energy into an electrical signal to ring your wireless doorbell. You'll never have to worry about the push button running out of power or the hassle of buying unusual batteries. You'll always hear your chimes! IP64 WATERPROOF AND LED TIME DISPLAY - The IP64 waterproof rating makes the transmitter rainproof and weather-resistant, crafted from durable ABS + PC plastic. It functions reliably in temperatures between -20°C and +65°C. The LED time display screen, which shows the time when the receiver isn't ringing, can also be used as a clock. 38 MELODIES AND 4 VOLUME LEVELS - Choose your favorite sound from 38 different chimes and a volume you like from four levels (0-110 dB). The memory function of our wireless outdoor doorbell saves the last melody, volume level, and time after a power outage. 150 METER WIRELESS RANGE - The penetrating wireless chime signal can transmit up to 150m/492ft, even with multiple obstacles (doors, walls, intermediate floors) in an open and long room. Loud enough to hear the doorbell clearly in every corner of the house. EASY TO USE - The transmitter can be attached to the wall by the front door with the adhesive film, and the receiver can be plugged into an indoor socket. What you get: 1 * transmitter, 1 * receiver, 1 * double-sided tape, 1 * user manual. Product Descriptions: AUOPLUS wireless doorbell, saving you significant money and electricity every year! Because it requires no batteries or wires. Specifications: Easy to install chime with 1 engaging signal 150m remote control, stable signal 38 melodies to choose from and 4 adjustable volume levels Self-generated electrical design, simple and convenient to use Advanced mirrored digital time display, exclusive atmosphere Multiple Uses: Option for multi-family homes For elderly family members in an adjacent apartment Wireless doorbell for warehouses, offices, hotels, factories, etc. What you get: 1 * transmitter (self-generated electricity) 1 * receiver 1 * double-sided adhesive tape 1 * user manual in German IMPORTANT NOTES: 1. The doorbell receiver must be plugged into the socket to adjust the ringtone melodies and volume after pairing (refer to the user manual). 2. The wireless doorbell has a programmable memory function. You can record volume, light, and ringtone melodies. 3. It is possible to pair multiple of these doorbells so that, for example, there is one doorbell at the front door and one at the back door. The two chimes are synchronized with the melodies, but the timing may differ slightly.