With the celestron powertank 17 you can take your telescope anywhere'. '.strtoupper('t')his portable, rechargeable power supply gives you extended observing and imaging sessions with 17 amp hours of power in one convenient package'. '.strtoupper('y')ou can use the included removable red flashlight until your eyes are dark adapted to find accessories and reference star charts'. '.strtoupper('w')hen the session is finished, the powerful led spotlight illuminates your observing area so you can pack up quickly and safely, without leaving anything behind'. '.strtoupper('t')he extra large celestron powertank 17 is more than just a telescope accessory, it can also be an essential assistant for your next outing because it can be used to charge drained electronic devices with a cigarette lighter adapter'. '.strtoupper('t')he powertank also comes with a built in siren and am fm radio for emergencies'. '.strtoupper('f')eatures 17 amp hour power supply for your celestron telescope 2 x 12v dc output car jack socket built in am fm radio and siren built in 2 usb ports for charging portable devices removable red filtered flashlight with magnetic back energy efficient led spotlight handy jump start system built in circuit breaker for safety cigarette lighter adapter included switchable 110v 220v ac adapter powertank 17 compatibility list will power any computerised mount compatible advanced vx cgx l astro fi cpc, cpc dx cg 5 nexstar evolution cge nexstar gt cge pro nexstar se series cgem ii nexstar slt cgem, cgem dx skyprodigy lcm series cgx