The Philips HF3431 goLite Blu Cord/Cordless Energy Light is designed to boost your mood and energy with proven bluewave light technology. The light is eye-safe and 100% free of UV light. Use anywhere, at home or on the go. There are 5 light intensity settings and a built-in digital timer with alarm and auto shut-off. Research shows 70% of users felt their energy levels improve after 2 weeks of use. Long lasting lithium ion battery. Automatic universal voltage (100-240V). 2 year manufacturer's warranty.