Designed for K03 family of sharpeners.

The attachment consists of a whole-milled aluminum body and an internal brass cylinders and provides a uniform change of angles across the entire width of the secondary bevel, producing a convex lens shape. As the abrasive moves along the secondary bevel from the cutting edge line to the knife spine, the sharpening angle decreases. The attachment is suitable for any thickness behind the edge of the knife.

It is quick to mount on the abrasive holder with a rod diameter of 6 mm. The Ultra attachment allows you to set and fine-tune any sharpening angle offset in the range from 0 to 90 degrees. It is adjusted by bending the two rods relative to each other. 

The laser markings are approximate indications of the degree of angle curvature and are not intended for precise angle setting. Use of an electronic angle finder to accurately set the convex angle range is highly recommended.

The attachment is mounted in the gap between the abrasive holder and the guide rod and is secured with 2.0 mm hex set screws. The fixing holes have a special shape to ensure that the rod is fixed on three points to eliminate any backlash.

To set the convex angle, loosen the 3.0 mm hex locking screw and adjust the inner cylinder to the required position.