As everyone has stated, it's expanding action brackets but since it is beyond warranty the customer will have to pay. The last brackets I bought were $100 + 10 s/h. Replace the end brackets first (you don't even have to remove the stack), this will help to keep things indexed. Then replace the center ones, reinstall the stack and look to see if veneer shims are needed under them. If your lucky, rep spring tension and checking will be OK but let off and drop will need to be adjusted -- Regards, Jon Page
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