ðə bɹˈɛtən plˈɑːɾɚ kəntˈeɪnz ɐ ɹˈuːlɚ wɪð ɐ ɹoʊtˈeɪɾɪŋ pɹətɹˈæktɚ ðæt sˈɜːvz æz ɐ kˈʌmpəs ɹˈoʊz, ɐlˈaʊɪŋ nˈævɪɡˌeɪɾɚz tə plˈɑːt ɐ kˈoːɹs ˌɔn tʃˈɑːɹts baɪ ɐlˈaɪnɪŋ ðə nˈɔːɹθ ʌvðə ɹˈuːlɚ wɪððə nˈɔːɹθ ʌvðə tʃˈɑːɹt.
The Breton plotter contains a ruler with a rotating protractor that serves as a compass rose, allowing navigators to plot a course on charts by aligning the North of the ruler with the North of the chart.