Celestron Nexstar 4SE Telescope and PowerTank LT Lithium Battery was $778.95, now $598.95 on Amazon. Save $200 on an excellent catadioptric telescope that now comes in at an excellent discount.

The Celestron PowerTank means you can leave the spare batteries and your flashlight at home. (Image credit: Amazon) Key Specs: The Lithium metal battery will last for up to 2000 charge cycles.