The Concord 850 Slim Line is a simple plastic 35mm viewfinder camera made by Concord Camera Corp. Produced in China this camera has a fixed focus "Japan optics" 34mm 1:8.5 lens with a single leaf shutter speed of 1/100. Manual gives a purported focal range is 4ft to infinity. 2 AA batteries are required to operate the manually powered flash but the camera will work without them. There is no light metering or lo-light circuit. Shutter advance is by a push lever more akin to those seen on 110 camera but not uncommon on Concord 35mm cameras.
In the UK it was also sold as the SnapJack purportedly the Union Jack Camera Co (in fact a brand of the UK Division of Concord). This was aimed at tourists and features a Union jack on Front plate.