KATANA FRET LEVELING SYSTEM is a system designed for leveling the frets, or the fretboard, under real strings tension on a straight or bowed neck. It offers the highest precision because it can level straight and it can also help to create the ideal progressive curve needed by the strings for best playability. Fret leveling with the strings on and tuned to pitch with the correct neck relief allows to level the frets with best accuracy while removing the minimum amount of fret material. With the KATANA you can level the frets on your bench or using it with the instrument placed in playing position with the same results. Your choice. Watch this Buzz Killer video to get an idea, they are same family tool. Katana can be adjusted in order to match the relief of the fretboard or it can be used straight. The complete leveling with this tool can take a few minutes. The system includes a special string raiser that helps to unlock the movement of the tool (if needed) without altering the balance of the neck and 3 special gauges (original Rectifymaster concept) that will help to match the tool and the neck accurately. It comes preloaded with #320 grit abrasive plus a recharge roll. This ultra-innovative system is a RECTIFYMASTER exclusive.
This system can be arranged with two different materials on its base (1 non-abrasive and 1 abrasive). They are arranged to be PLANAR. The BUZZ Killer tool has been provided with both materials arranged planar since 2011. It has been covered also in the Online Manual provided to worldwide customers since 2011. Described is a method for arranging or adjusting different types of materials in a unique planar surface toward the frets/fretboard/fingerboard. A method to check the level of said materials against another planar surface with a source of backlight has been provided since the beginning (2011). Here is the BUZZ Killer manual which still includes how abrasive and non-abrasive materials can be arranged to be planar.
The Katana Fret Leveling System is protected under U.S. Patent number 9,224,369