C-Thru ruler co. USA.. The Vintage P-71 Corse Protractor Plotter Ruler is a unique and collectible piece for boat enthusiasts. This 4''x15'' ruler, specifically designed for navigation on boats, features intricate protractor markings for precise plotting and measuring. Its vintage design adds a touch of nostalgia to any collection, making it a valuable and functional item for those passionate about boating and ships.
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