Applicable model: Microsoft 12.2 inch Surface Pro 3/Pro 4/Pro 2017/Pro 6/Pro 7 Product size: 295 * 220 * 5mm Packing size: 380 * 251 * 15mm Product weight: gross weight 440g, net weight 280g Product model specifications: 1. Bluetooth 3.0 standard interface 2. Effective operating distance: 10 meters 3. Modulation mode: GFSK 4. Working voltage: 3.0–4V 5. Working current: less than 2.5mA 6. Standby current: less than 0.3mA 7. Sleep current: less than 40uA 8. Charging current: greater than 200mA 9. Standby time: more than 100 days 10. Charging time: 2–3 hours 11. Lithium battery capacity: 350mAh / 550mAh (backlit) 12. Sustainable working hours: 35–100 hours 13. Lithium battery life: 3 years 14. Button force: 80±10g 15. Key life: 5 million clicks 16. Operating temperature: -10°C to 55°C Bluetooth pairing steps: 1. Turn on the Bluetooth switch on the tablet. 2. Press and hold the power switch on the keyboard until the indicator light flashes. 3. "Bluetooth Keyboard" and a four-digit code will appear on the tablet screen. 4. Enter the four-digit code as prompted on the screen. 5. The wireless keyboard is successfully connected. LED status indicators: 1. Power and Bluetooth connection indicator: After pressing for three seconds, the light flashes to indicate Bluetooth pairing mode. The light turns off automatically after successful connection. 2. Caps lock indicator: The light turns on when uppercase input is active. 3. Charging indicator: Indicates charging status. 4. Low battery indicator: The light flashes when the voltage drops below 3.2V, indicating that charging is required.