Power your motorized/computer-controlled telescope with Celestron's PowerTank 17 17 Ah 12 VDC Power Supply. This versatile accessory features two 12VDC car/vehicle plugs to power the telescope and peripherals, plus two USB ports to charge small electronics such as phones or GPS sets. To help get you to your observation spot, it is equipped with a powerful spotlight, and when you're setting up, remove the smaller magnetic-backed red-filtered flashlight to light your way without effecting your night-adjusted vision. A built-in circuit breaker protects all your equipment and devices from damage.  This version of the PowerTank features a built-in AM/FM radio and a siren for emergency situations.