I found the following posted on the Victorinox website. It's a google translation so may not be perfectly clear but interesting nonetheless:
Metal file version until 2006
The teeth of the metal file are brought by a complex striking procedure into the material (case-hardening steel). The material has the characteristic to develop by the hardness process high surface hardness with soft core. Since this steel alloy is not corrosion resistant, the file must later be chromium plated.
Metal file new version starting from 2006
Contrary to the old version with the new version stainless high-grade steel is used, with which the for sale and Sägezahnung on a highly precise machine are ground in. The metal file became more substantial by the change in geometry.
This change will flow gradually in the production of new bag Tools. By the high claims of quality at functionality, Design and finish, Victorinox strives to protect its prominent position on the world market.
Hereby I hope to have answered your question. For further information I am to you gladly at the disposal.
Friendly greetings from the Swiss Knife Valley
VICTORINOX
Leader quality assurance
Robert Elsener
Metal file version until 2006
The teeth of the metal file are brought by a complex striking procedure into the material (case-hardening steel). The material has the characteristic to develop by the hardness process high surface hardness with soft core. Since this steel alloy is not corrosion resistant, the file must later be chromium plated.
Metal file new version starting from 2006
Contrary to the old version with the new version stainless high-grade steel is used, with which the for sale and Sägezahnung on a highly precise machine are ground in. The metal file became more substantial by the change in geometry.
This change will flow gradually in the production of new bag Tools. By the high claims of quality at functionality, Design and finish, Victorinox strives to protect its prominent position on the world market.
Hereby I hope to have answered your question. For further information I am to you gladly at the disposal.
Friendly greetings from the Swiss Knife Valley
VICTORINOX
Leader quality assurance
Robert Elsener