Doorbell design with 36 ringtones and 5 welcomes doorbell rings for personal preferences. 4 levels volume adjustable(Loud/ High/ Middle/ Low ) from 113~25dB. Welcome, alarm, doorbell and night light mode, 5 in 1 automatic door chime. With 4 colors LED light, Color/ Red/ Blue/ Green can distinguish multiple entrances by different light colors. The transmission range is up to 280m/918ft and detection range approximately 2~8m/ 6.6~26ft to effectively keep you alerted.(Please note that this not waterproof.Keep it away from rains or cover adequately.just place the sensor at the entrance to your driveway and the receiver inside your home.) Place the receiver indoor and put the sensor at other places, such as door entrance, home mailbox, driveway, walking paths, apartment, office, hotel, store, and many other indoor places. Receiver is self-adhesive installation, the detector is wall mounted. Use batteries or micro USB power supply. Before using, please read the manual carefully and put in batteries (not included), adjust the sensor's angle to avoid false alarming.