A special blade steel is used for both cutting
blades, made of stainless chromium
and molybden-alloys. After hardening at
1,040 degrees and tempering at 160 degrees,
the blades have a hardness of RC
56 (RC = Rockwell C, unit of hardness).
The wood saws, scissors and nailfiles have
a hardness of RC 53, the screwdrivers, tinopeners
and reamers RC 52, and the
corkscrews and springs RC 49.
The metal saw and file is case-hardened
and hard chrome-plated, so that even iron
and steel can be sawn or filed.