Just opened up the package for the top chain slippers for my 3.4 and have decided that they are going back to the supplier for credit. There is a very definite line in the steel where it has been bent at 90 deg, rather than the old ones that have a nice 2-3mm radius, fairly sure I have seen this discussed before on the forum but haven’t been able to bring it up on the search engine 
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Thanks David, that was the thread I was searching for, just used the incorrect search words.
I have contacted the supplier and am awaiting their response.
I have added the photos comparing the original to the new items. I have ordered another set from a different supplier in the hope that they use a different manufacturer, fingers crossed, otherwise the old ones are going back in 
I wonder if there’s a company that can simply reline the old ones. Does anyony know what the process involves?
Interesting thought, its originally manufactured so reverse engineering should be a possibility, something like a strip of PTFE perhaps ?
Years back, I found a company —no idea where—who did rubber bonding like this: it was NOT cheap.