This convenient and cost-effective wireless chime set includes two receivers and one transmitter. The transmitter is self-powered by the force of being pressed, eliminating the need for battery replacement or wiring. It can be installed anywhere, making it versatile for use at entrances, nursing homes, and more. 【Clear Notifications with Light & Sound】 The high-sensitivity receiver provides a communication range of up to 150m (over 30m through walls). It can be used reliably in large homes. There are 32 call melodies and 4 volume levels. The sound and light notifications are designed to be user-friendly for those with visual or hearing impairments. There are 3 operation modes: "Sound + Light," "Sound Only," and "Light Only (Silent)." You can easily switch modes by simultaneously pressing and holding the volume and selection buttons. 【Interference Prevention & IP44 Waterproof】 The transmitter is designed to minimize interference, ensuring stable wireless communication. The IP44 waterproof design allows for use near outdoor entrances and bathrooms. 【Wireless & No Wiring Required】 Simply plug the receiver into an outlet. The transmitter requires no batteries or power and can be easily installed with double-sided tape. No wiring is needed, so it can be used immediately anywhere. 【Shapes Available】 This product is available in two shapes: "Rectangular Type" and "Round Type." Please select your desired shape when ordering.