Wireless Doorbells Battery Operated Self-adhesive Rings Transmitter Specifications: Material: ABS Color: White+Blue Receiver Power Supply: 2 x AAA Battery (not included) Transmitter Power Supply: 1 x 23A Battery (not included) Music: 16 music songs optional Size: (L)X(W)X(H) Transmitter: 7.8x4.3x1.7cm /3.07"x1.69"x0.67"(appr.) Receiver: 10x5x3cm /3.94"x1.97"x1.18"(appr.) Features: ● Simple and flexible wireless installation design eliminates the hassle and expense of installation and saves money. It does not affect the decoration and appearance. ● Up to several tens of meters to meet the needs of various residential and high-rise buildings. ● Built-in stereo speakers make the sound crisp and sweet, especially suitable for home, office, factory, tourism and other places, for a wide range of uses. ● Strong anti-interference ability and low repetition rate. Package Included: 1 x Transmitter 1 x Receiver (excluding other decorations) Instruction is not included. Please feel free to contact us if you have any questions. Hope a nice day! Notice: Please allow slight deviation of measurement due to manual measurement. Due to different producing batches, product details might be a little different. Due to different monitors and different light, the picture may not reflect the actual color of the item. Please consider the actual sizes shown in the listing as the pictures are generally enlarged to show detail.