Old rubber typewriter feet turn rock hard, or become a sticky mess. They don't make your machine stay at the same place while typing. Keeping these feet will result in the machine sliding all over the place. So to make sure that the machine doesn't move, and/or scratch your typing surface, it is advisable to install new feet.

I started making feet for the machines in my own collection, and was so satisfied with the results that I decided to make these available to everyone.