INCREDIBLE TECHNOLOGY: Guaranteed to work every time!We use a state-of-the-art self-feeding mechanism that is reliable, robust and efficient. also, the extended antenna gives you an excellent range of up to 150m in open fields.In addition, the doorbell is quite simply one of the smallest and most discreet currently available on the market. Interference with your alarm or your gate badge Impossible with our wireless, battery-free doorbell! Why The radio frequency channel used is not universal like on battery-powered wireless doorbells, it is a codespecial that works exclusively with our equipment, so no risk of ringing in the middle of the night ECONOMIC AND ECOLOGICAL: Save money with your wireless, battery-free doorbell! In winter as in summer, your IP65 wireless doorbell will work.Unlike transmitters with batteries which will consume a lot of battery power, particularly in winter as it is well known, batteries do not like the cold at all. In addition, by avoiding battery changes, you are making an ecological gesture by avoiding the long and complicated recycling of batteries.