Precise 24-hour time setting: The integrated digital USB timer supports flexible countdown adjustment of up to 24 hours for USB-powered devices. Customize the shut-off time for fans, lights, chargers, or small appliances. Materials and construction: This pack of 2 USB countdown timer switch cables consists of copper conductors and an outer sheath. Energy-efficient operation: Devices are automatically switched off after the preset time, reducing idle power consumption. Connect the timer cable to a standard USB port, attach your device, and set the countdown on the digital display. No additional programming or software is required. Suitable for use at home, in the office, dorm rooms, or while traveling with various 5V USB-powered products. Design: Each USB timer cable measures approximately 20 cm. Color: Black. Material: Plastic. Package Contents: 2 x USB Countdown Timer Switch Cable. Note: Image color may vary due to lighting and display settings. Measurement may vary within a range of +/- 1-3cm.