- Male side: M42 X 1mm - Weight: 20 g - Material: metal EXA-M42 ring mounting method as follows: 1, the connection ring mounted on the rear end of the lens; 2, Use a screwdriver to tighten the three screws on the ring; 3, Connect the focusing tube and install the lens body, lens aperture can be visually on the 12 o'clock position, if position deviates, loosen three screws and turn the lens to an appropriate position, and then tighten the screw that is ok.
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