Fangrui Product Details [rechargeable Battery With Usb Interface Design]: Built In 3000mah Rechargeable Battery, The Reading Lamp Can Be Powered By Usb Charger, Plug And Play, Notebook Pc Usb, Mobile Phone Adapter, Car Usb And Etc. You Can Use Anytime, Anywhere. [enjoy Your Night Time]: The Book Lamp Is For Working, Reading, Study, Camping, Playing Computer, Crossing . You Can Change A Suitable Color For Night And Not Bother Others In The Home. The Book Light Is , Hotel, Office, On Car, Airplane, Etc. 4k Color Rendering: Restore High-definition Colorful Colors Color Rendering Index (ra 97) No Blue Light, No Flicker Mouth Design Can Be Used To Clamp Anything. It Adapts To The Changing Usage Environment Of The Campus. The Clamping Mouth And Clamping Force Have Been Greatly Upgraded. Three Levels Of Color Temperature/short Switchwhite Light(6000k)white Light (4500k) Warm Light (3000k)warm Light Stepless Dimming/long To Control Brightness Brightness Stepless Adjustment +brightness Dimming Method: Tap To C