Strong signal It can penetrate 3-4 walls and wireless range up to 150 meters in open area, great forlarge house including villas, apartment, offices,shops,warehouses.etc. 32 Ringtones and 4 Adjustable Volumes: The wireless doorbellofters a ide selection of32 melodies and 4 volume levels to meet your needs for dliferent occasions. The wireless doorbellofters Flashing, ight with audioalert indicators which is easy for people including the hearing impaired to notice. Built-in CR2032 button battery. Frequency:433Mhz Plug Type:EU Plug,it applies to Indonesia, Germany, France, Spain, Italy and so on. Voltage:AC220V Colour:White Material:Plastic Package Contents: 1 * transmitter 1 * receiver 1 * screw pack 1 * sponge sticker 1 * English instruction manual 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.