You have probably tried the chair leg felt pads already, and know that they can only help for a short time. And so, you have to buy them again and again, and it never stops. Maybe the silicon or rubber caps will last for longer but these are not slippery, so it is difficult to move chairs. And they are not tight as well, therefore the size should be the exact as a leg of your chair.
So stop wasting your money! Buy the everlasting product just one time.