【1 Transmitter, 2 Receivers】Very loud volume, 7-color bright flashing lights. This long-range wireless doorbell is perfect for families and offers one-button calling for added security. The transmitter and receiver connect wirelessly. When the button is pressed, the receiver plays beautiful music and flashes seven colors simultaneously, ideal for those with hearing or visual impairments at night. The doorbell's volume is adjustable (4 levels) and audible within a 150-square-meter radius. No matter the size of your house, you won't miss visitors. Low energy consumption, environmentally friendly, and energy-efficient design. It uses only 7 AA batteries (3 for each receiver and 1 for the transmitter) and lasts 3-5 months. Safe and reliable, suitable for various environments, and unaffected by rain or strong winds. Easy installation. This doorbell doesn't damage walls; it uses double-sided tape for easy application and removal, or can be installed with screws.