Mighty Bright Black XtraFlex 2 LED Book Light Two bright white, energy-efficient LED, Individual switchs allow light control Precisely engineered optical grade lens spreads light evenly Free-standing base 3 AAA batteries (included) Two energy-efficient LEDs cast bright white light Durable LEDs last 100,000 hours - no replacement necessary Use one or two LEDs by tapping button Sturdy clip grips almost anything