OLFA® EXCEL BLACK™ takes blade sharpness to the next level. OLFA's secret, advanced production process makes this blade 25% sharper than ENDURANCE™ blades (which are already very sharp!). You can really feel the difference as your cutter glides through the cutting surface with ease and precision. Not only do the blades last much longer than conventional blades, they give you clean cuts that show off the quality of your work. They will even cut through wet, pasted wallpaper without dragging or tearing it, where another blade would have great difficulty. The 9mm EXCEL BLACK™ blade is 0.38mm thick and has 13 snap segments.