I recently got a retrofit sostenuto rod from WNG for a 1913 Mason & Hamlin BB which had a broken brass post.
One hint - there are small black screws that for one of the adjustments that was difficult to get to with a screwdriver.
Replaced with, I believe M6 (metric) hex screws, and also got a matching hex key.
Attached the key to the interior of the action cavity for the 'next guy' who may need to adjust.
Job is not for the faint of heart... I think I redid the dampers a few times to get it right, but it works.
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Michael Hagen RPT
Rohnert Park CA
(707) 664-9857
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