This is a protractor head for a Starrett combination square. I actually have a modern Starrett combination square, and this did not fit on it. So, I suspect it's for an older model of combination square.
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Starrett Combination Square 5pcs Head, Protractor no. 492, center Head, 12" rule & scribe works great
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06256-M Blade (Narrow) Only for 457M Diemakers Square.
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No. 20 Machinist Square Tool as seen.
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The Starrett Wood Case is a precision tool designed for inspection and measurement tasks in metalworking, for a 4 1/2” square . Made of durable wood, this case is ideal for protecting and storing various square tools, such as 20 or 55 triangles. Crafted in the United States by the reputable brand Starrett, this wood case ensures quality and reliability for professionals in CNC, metalworking, and manufacturing industries.
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Blade Only For Combination Set. 35 - mm and 1/2mm Both Sides.
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