The premium MP3 wireless gong or wireless doorbell set includes a gong with a blue LED light signal and a bell button with an LED light signal. There are 30 different melodies to choose from and the option of transferring your own MP3 music tracks to the gong using a USB cable. Gong installation type: surface-mounted (wall, front door) or freely positionable (table, shop counter). Bell button installation type: surface-mounted using a screw or adhesive strip. Wireless range: 200 meters in open space. Volume: 80 dB at 1 meter. Gong power supply: 2 x 1.5 V AA batteries (not included). Bell button: power supply: 1 x 3 V battery (CR2032) included. Frequency band: 433.05 - 434.79 MHz. RF power level: 10 mW. Protection class gong: IP 20. Protection class bell button: IP 54. Color: pure white or aluminum. Parallel connection of several gongs possible. A maximum of 4 bell buttons can be coupled with one gong. Connection of the IR motion detector (order no. 094280 possible)