28D stamp on S380-29 channel balance

A handy person from Sarasota Fl says:
I can't seem to find a stamp on this balance that matches any of the numbers in the options. The numbers and letters I do see are 28D USB.
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Tom from SWISCO responded:
For the S380-29 , a stamp of 28D usually corresponds to our 2840 option. However, you should weigh your sash and check the chart on the S380-29 store page to confirm that this is correct.
A handy person from sarasota fl says:
Tom,
Thank you for your prompt reply to my question.
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