More information· 18mm cutting blade · Presentation in a plastic box of 30 blades with belt clip · For cutters: L-1, L-3, L-5, L5-AL, NL-AL, PL-1, EXL, BN -L, OL, CL, LL, ML, CS-2, CMP-2, BSR-200, BSR-300, BSR-600, NOL-1, XL-2, DL-1 · Made of superior quality steel. · All Olfa blades go through a process of adjustment of hardness, sharpening angles, dimensions and other conditions in order to obtain the best balance between initial sharpening and long service life. · Difference between silver or black Excel Black blade: The blade Traditional silver is slightly less sharp but with a longer life and the Excel Black blade is sharper but with a slightly shorter life.