Colorful light, can adjust brightness, 4 mode choices (red light/blue light/green light and LED Flash). Remote transmission, 280 meters in open place, suitable for more places. Detection range of the sensor approximately 2-8m. You can put the sensor at the porch, , mailbox and put the receiver in your house. Built in 8 chord music chips, 40mm speaker, more pleasant, more loud. Selectable Ringtones. The receiver is a doorbell design with 36 different ringtones from melody sounds to simple basic for personal preferences and 5 welcome for business use. alarm speaker, maximum 113dB, can effectively deter thieves. Application:For business welcome , a big mall with various gates or small retail store may need the detectors to transmit rings when guests come in. For the , alert you when someone is approaching your driveway/porch//garage door. Also can used to monitor the elderly or child, who live separately or needs help. Put it to the mailbox door, the chime will work when you have mail in your box. No more walking out every hour to see if your mail is there. Applicable to all kinds of shops, clubs, hotels, offices, factories, homes, , store,garage, supermarket, ,villas and other places 4 levels of volume can be adjusted, have memory function when change the battery. Color:white Material:ABS Package Contents: 1* Receiver 1* Sensor Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.