This is Derek the one who sent you the scope, Im glad you liked it so much! When I got it on ebay the seller had it advertised as untested/non working, lucky for me when I got it everything worked like a charm. Some one has modified it slightly, the BNC connector on the back is not original to the design but seems to work. It didnt have the internal battery when I got it, but should be easy enough to replace if you wanted to use it cordless. Ive had the covers off it before so I know what it looks like inside, but it will be interesting to get a more technical look into its construction and operation.