The Leica IIIf was Leitz's (later Leica) first 35mm camera body for screw mount lenses with built-in synchronisation . It succeeded the Leica IIId, which was a rare variant of the Leica IIIc. Built-in synch means that, unlike its predecessors, the IIIf didn't need an optional rework for flash photography. But flash synchronization still needed an extra adjustment, a contact number between 0 and 20, which depended on the type of flash bulbs used. That was necessary since different types of bulbs needed different flash firing delay times for exact synchronization.
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The camera with caps.
Cosmetic: Overall good condition, with some signs of use.
Optical: Free from haze/fungus/scratches.