<p>This gear fits LOMO OKS5-18-1 lens in Konvas housing with OCT-19 mount.</p> <p>It is purposed to replace original focus ring, though this procedure is bit more complex than installation over the original ring.</p> <p>Please refer to pictures to learn the replacement procedure:</p> <p>1. Remove stop screw from the lens barrel.</p> <p>2. Rotate focus ring counterclockwise till inner block is decoupled (you'll make 9-10 full turns).</p> <p>3. Remove the inner block. DON'T TURN FOCUS RING NOW AND FOCUS GEAR LATER TILL STEP 8.</p> <p>4. Unscrew three screw holding the focus ring.</p> <p>5. Remove the ring and mount the gear instead of it.</p> <p>6. Put the three screws back to secure the ring.</p> <p>7. Insert the optical block into the housing taking note of alignment plate and slot.</p> <p>8. Rotate focus gear clockwise till stop.</p> <p>9. Put the stop screw back into the housing.</p> <p>10. Check distance scale to make sure that it rotates in correct range.</p> <p>11. Put the lens onto a camera and make sure that focus is correct. If not, remove the stop screw and rotate focus ring clockwise one turn; put the stop screw back. This step will not be necessary most probably though.</p> <p>That is all.</p> <p>Dimensions:</p> <p>Inner diameter - 65 mm;</p> <p>Outer diameter -83 mm;</p> <p>Thickness - 8 mm.</p> <p>Mod - 0.8 mm (pitch 32).</p> <p>& </p>