Well, I found the part number, but not in a way you may have expected, seeing as I am lazy and not wishing to go out to the shed in the garden to grab my small screwdrivers, I took a photo of it, with a view to posting it here, however as the flash cut in the photo showed up the finer details of it, one being the worn off model number as if it was clear as pie, yet in daylight nothing can be seen......Need to see if it is still supported by spares now... BTW mine is the HQ6859 one.
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