This mini button is designed for caregivers and patients or elderly or residents or disabled or sick for freedom while still being able to call for help at home. No need to shout to get someone's attention. Features: - Color: As shown. - Material: ABSandAluminum. - Size: 8.1 x 8.1 x 4.5 cm. - Working distance: 80 meters - Working frequency: 433MHZ - Power supply voltage: Receiver: 90-250V transmitter: 3V 2032 battery. - Made of durable materials, easy to use. - Makes emergency situations truly audible loud design makes people more attentive for faster help. - Can also be used as a simple doorbell. - Battery-powered, easy to use. Warm tip: Dear buyers, due to lighting effects, monitor brightness, manual measurement, etc., there may be slight differences in color and size between the picture and the actual item. We sincerely hope you can understand! Thank you! Package List: 1 x Receiver 1 x Transmitter