Introduced in 1930 with the pre-Standard Leica camera body, the 3.5cm (35mm) f3.5 is the very first interchangeable accessory Leitz/Leica lens that Berek designed for the Leica system, a system that over the next few decades was to become the roadmap for where most of the world of photography equipment was to go.

The early production for the non standard Leica I in 1930 was individually fitted and matched to the particular body for which it was intended. The serial numbers were internally scratched or engraved. The external mount, however, bears a 5 or 3 digit number which relates the serial number of the Leica I (non Standard) camera body to which it is matched. At first the full SN of the camera body was employed then only the last 3 digits.

In 1931, when the Leica Standard was introduced, production of the new compatible screw mount distance was designated by an engraved "O" on the lens mount. In 1932 the rangefinder coupled cam was added. All early production is in nickel plated mount until 1933 chrome was added.

Optical coating which improved contrast/optical performance was incorporated in 1946.

Optically, extremely good for its era, the lens is very fine at f8 and smaller but less than excellent by modern standards wide open.