This camera requires a 2x CR123 battery (Not Included). 
The special feature of the camera is its lens, or rather the two lenses. It has two superimposed lenses with different focal lengths (35 mm f3.5 and 70 mm f6.3).Now, if you want to shoot a distant subject, you switch to the 70 mm lens. In short, a very simple zoom. Another special feature at the time was the water resistance of the Olympus AF-1 Twin.Otherwise, it is very similar to other compact cameras of the time. Thus, it works practically without much intervention from the photographer. It finds out the film speed by DX coding, then it sets the exposure by itself and the film is also transported automatically.

Check some Olympus AF-1 Twin 35mm Film Camera pics HERE.