Specification: Material: Tungsten Cemented Carbide Length of blade: 12mm Length of holder: 51.8mm Degree of Blade: 30 / 45 / 60 degree Package Includes: 1 x Blade holder 10 x 30 Degree Cutter Blade (Yellow) 10 x 45 Degree Cutter Blade (Red) 10 x 60 Degree Cutter Blade (Blue) Tips: 1. Blade should not extend too long, generally within half a millimeter is better, while paying attention to extended blade longer properly when carve the small print, in order to avoid the blade holder take the carved strokes away. Suitably engraved small print with new cutter and slow down. 2. When the word carved with angular phenomenon, you should change the blade to eliminate the problem, if the phenomenon persists after change blade, it should be the holder problem. 3. When problem arise the blade holder, try a drop of oil in the bearing and rotate the blade several times to lubricate, if still unresolved, consider replacing the blade holder.