I just got my front and rear Mintex 1144 pads. I'm wondering if the rubber pieces are shims? Anybody know. As a mechanic I am very familiar with aluminum shims, "blue goo", anti squeel. What came with both sets of pads looks like generic shims a little larger then a business card (length & width) one side has a peel of adhesive side, what is different about these is they appear to be rubber. Just like a patch for a bike tire but larger, never worked with these before. Any input would be appreciated.