I purchased this for $25 thinking I was going to buy a friend's Nexstar 11 GPS, but the money for the scope ended up going to fix our car so I just don't need this adapter.
This is the Celestron AC Adapter, Item #18773, brand new in the original box. It is powered off of standard 110-volt AC and outputs 12 volts DC. It is rated at 1.5 amps. This accessory is compatible with all NexStar products (also compatible with Celestar 8, Ultima 2000, CI700). This adapter is not compatible with the Advanced or the CGE products, which require 2 amps.
I'm selling it for $18 shipped in CONUS. Prefer payment via PayPal, but will also accept cashier's check or money order. Please feel free to contact me with any questions, thanks!