400 M/1300 FT LONG WIRELESS RANGE -This wireless door bell can reach up to 400 meters in the open space without interference, and the transmission distance of the partition wall is 20-80 meters, which can cover almost the whole house., EASILY DISTINGUISH VISITORS -With 48 melodies, it can set music for different house entrances, easily distinguish visitors from the front and rear doors, and it has a 110DB alarm sound that can ring loudly when needed.and this door bells has 5-level, IP54 WATERPROOF WIRELESS DOORBELL -No fear of wind and rain, low temperature resistance, this wireless doorbells can be used in the outdoor temperature of -40 ℃ to 70 ℃, calmly deal with all kinds of bad weather, so that you will not miss any visitor, DOORBELL BUTTONS -It is both a doorbell and a wireless pager. Select specific music and use the lanyard to hang the doorbell button around neck or hand, and you can call someone for help when you need it, loudly and convenience., INSTALLATION & MAINTENANCE FREE -The wireless battery doorbell can be used directly when it is plugged in. Use screws or double-sided tape to fix the doorbell button. The high-capacity lithium battery can be used for about 3-5 years, and it is safe a
