Meriden Fire Arms Single Hammerless Trap Gun, 1912
"Lyman ivory front and rear shotgun sights"

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I looked through the Baker SBT ads and catalog listings I have and there was no mention of a mid-rib bead even in 1921.

I had a 1918 (2nd year production) Parker SC with front and mid ivory sights.

1915 Ithaca SBTs no mid-bead

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1924 Victory grade with "Front and rear brass sights"

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