This is the first working prototype of many, a protractor adapter for your standard 18 cork backed ruler. It adds a pivot point along its…

Angle Measuring Equipment Choose Vintage Square or Craftsman Universal Protractor Plum and Level 9-3995

Pacific Arc Professional Acrylic Protractor

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Six inch transparent protractor., Features rounded corners, tapered edges, and dual scale for measuring both left- and right-opening angles. Shatter

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Pacific Arc Professional Acrylic Protractor is made from high quality acrylic for sturdy use., Etched Graduations, Accurate down to a single degree.,

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