[4 LEDS IN TOTAL and 3 LUMINOSITY LEVEL:] 2 LEDs per arm, 1 spotlight and 1 spotlight per side. The first click is illuminated, the second click is a spotlight, the third click is a spotlight and both spotlights, the fourth click is disabled. The functions are the same for each arm. Topnma neck lamps can meet your different lighting requirements.[USB RECHARGEABLE:] Built-in 8500mAh battery, supplied with USB charging cable. The book lamp only takes 3-4 hours to be fully charged and can last up to 7-8 hours with high brightness and 10 hours with normal brightness.[BENDY AND FLEXIBLE ARM:] This LED book light has flexible arms that easily select the best angle for your needs. Soft silicone coated, non-toxic, safe to use and high quality. Perfect for reading in bed or in the garden / on the patio, for walking, for repairs, crafts, work, knitting, etc.[LIGHTWEIGHT and COMPACT:] Weighs only 0.15 kg, the flexible neck light does not take up much space and fits easily in your suitcase. This makes it an ideal choice for a portable reading light.