GNS2000 plus, a GPS receiver. I purchased it around August 2018 and used it for about two years, after which it was stored in a closet. By connecting via Bluetooth, you can use GPS on devices that don't have it. There is some paint chipping, but I think it's still usable. (I haven't peeled off the film on the glossy surface with the LED indicators, etc.) I have confirmed that it works with my iPad, iPhone, and Android devices. I feel that the battery life hasn't changed much. There are no instructions, but I can provide some support regarding connection methods via the transaction message. Please feel free to comment if you have any questions. Thank you.