Looks like it’s meant to help protect from irritation from the chinrest and some of its parts. Though, from the pictures, it looks like it doesn’t cover all of the pieces that might be causing irritation. What kind of discomfort are you experiencing? Have you been ale to pinpoint which contact with the violin is creating the problem? Might it be a technique issue?
Either way, here’s a link to the Strad pad. Whether it will help you depends entirely on your situation. Maybe I could help here with a little more understanding.