Energy Saving Portable 18W Emergency Desk Lamp Operates from AC Power (110 VAC) or from the internal rechargeable battery Heavy duty rechargeable battery provides over 4 hours of emergency lighting Automatic switches to battery power during usage when the AC power is disconnected Automatic recharges when AC power is restored Includes a bright 18W energy efficiency bulb rated 10,000 hours. Equivalent to an ordinary 80W bulb