GLL Portable LED Desk Lamp Touch Control, Battery Powered, USB Powered, Bendable Tube, Eye Care Dimmable Book Reading Light Table Lamp, Adjustable Brightness for Table Office Home Dorm (Blue) Dimmable touch switch, short touch on the switch of control panel, will turn off/on the lamp. Long touch the switch control panel, the lamp goes dim from bright,retouching it in ling time after loosen figer, the lamp will become brighter and brighter. Flexible gooseneck tube can be bended to any angle as you like The lamp can be power by 3 x AAA battery, and also can be power by usb ,it can connect to computer /laptop/power bank/ usb charger adapter. The usb cable is measures approximately 1.5Meters long and it can be an adequate length for normal purposes. The LED lamp puts out bright white light with a reported color temperature of 4500 Kelvin. If you like bright, clean daylight light this lamp offers just that. Long Life LED Bulbs, saving and money on your power bill with cost effective LED lighting