Features: 4 levels volume adjustable, 38 ringtones. strong signal, 150m long distance transmission. large button, easier to . push the button, immediate response, and change colors. Description (1) Working frequency: 433MHz (2) Music quantity: 38 (3) Output method: Horn (4) Demodulation method: ASK (5) Encoding format: EV1527 Material: Plastic Color: As shown Control method: Equipped with a remote control for control plug-in installaion, easy to use. emergy saving button, long-term standby combination, free matching Partition wall transmission distance is generally 15-20 meters Plug Type:EU Plug,it applies to Indonesia, Germany, France, Spain, Italy and so on Voltage: AC220V Package Contents: 1 x button 1 x receiver Only the above package content, other products are not included. Note: Light reflection 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.