The doorbell design comes with 36 chimes and 5 welcome doorbell chimes, which can be selected according to personal preference. 4 levels of volume adjustable (big/high/medium/low) from 113~25dB. ^ Welcome, alarm, doorbell and night light modes, 5 in 1 automatic doorbell. Equipped with 4-color LED lights, Color/Red/Blue/Green can distinguish multiple entrances through different light colors. ^ The transmission range can reach 280m/918ft, and the detection range is about 2~8m/6.6~26ft, effectively keeping you alert. (Please note this is not waterproof. Please keep it out of the rain or adequately covered. Just place the sensor at the entrance of the driveway and the receiver in the home.) ^ Place the receiver indoors and place the sensor elsewhere, such as door entrances, home mailboxes, driveways, sidewalks, apartments, offices, hotels, stores, and many other indoor locations. ^Receiver is self-adhesive mount, detector is wall mount. Runs on battery or micro USB power. Before use, please read the instruction carefully and install the battery (not included), adjust the angle of the sensor to avoid false alarms. Packing quantity: 1*host+2*sensor