Features: USB input 5V2A, CR2032 dummy battery output 3V1A, can replace a CR2032 3V battery. Suitable for CR2032 3V power supply, no need to change batteries frequently, saving money and being environmentally friendly. Can be powered by USB power supply, USB charger, computer, etc. Red line positive, black line negative, easy to use. 100 cm cable length, small size, light weight, easy to carry. Specifications: Material: Plastic Cable length: about 100 cm/39.37 inches/3.28 ft USB input: 5V2A CR2032 dummy battery output: 3V1A Note: Due to manual measurement, please allow 1-2 cm error. Due to different screen resolutions, please allow a slight color difference. Package list: 1 USB to 3V CR2032 dummy battery charging cable