SF109 Tree Texture Bluetooth Keyboard Leather Case For Microsoft Surface Pro 4 5 6 7(Black + Black) Features: 1. Not only a protective case, built-in Bluetooth keyboard, more powerful 2. The keyboard and leather case can be separated design 3. Bluetooth chip, fast speed, low power consumption, stable 4. Precise cutting, easy access to all buttons and ports, providing you with smooth operation 5. Support function, easy to use 6. Easy to insert and remove 7. Tablets are not included Specifications: 1. Bluetooth standard interface 2. Effective operating distance: 10 meters 3. Modulation method: GFSK 4. Working voltage: 3.7-4.0V 5. Working current: less than 8mA 6. Standby current: less than 0.3mA 7. Sleep current: less than 50 microampere 8. Charging current: more than 200mA 9. Standby time: more than 100 days 10. Charging time: 2-3 hours 11. Lithium battery capacity: 200mAh 12. Sustainable working hours: not less than 30 hours 13. Lithium battery life: 3 years 14. Button force: 80+-10g 15. Button life: 5 million clicks 16. Working temperature: -10-55 degrees Celsius 17. Charging port: Type-C 18. Weight: 835g 19. Product size: 29.8x21.4x2.2cm