Excellent DesignYou can install the doorbell receiver indoors and install the self-generating transmitter on your outdoor door, which allows your visitors to remotely ring your indoor doorbell via the outdoor door transmitter. Stable and reliable performance with high receiving sensitivity. Strong signal can pass through walls, floors, doors etc. The controlled range is about 150m. Easy to InstallThe plug-in doorbell receiver can be plugged into any socket in your home. And the waterproof kinetic transmitter can be installed on the outdoor door. No wiring request. This kinetic transmitter has a built-in small generating electromagnetic coil. A little pressure on this transmitter can generate a current that powers it. No battery request. 38 Melodies to ChooseA 40mm stereo speaker delivers rich and crystal clear sound; 4 adjustable volume levels with a maximum intensity volume level of 50 dB over 1 meter; pressing the music button allows you to choose between 38 melodies. More Flexibility This self-generating wireless doorbell is programmable and is compatible with DieseRC self-generating wireless remote control switch. Extremely easy to reset and program. You can easily add an additional wireless transmitter and a ringtone receiver yourself according to your needs. And also this doorbell can be linked with DieseRC self-generating wireless switch. Wide Application The products can be used in homes, farms, factories, offices, laboratories, supermarkets, etc. You will never miss a visitor.