“Inoue” and “Kent” types are available. 1. Inoue Type: Nautical Triangles, a position finder for the navigator, consisting of a danger-angle triangle (A) and a protractor triangle (B) made of transparent plastic, 36 cm. 2. Kent Type: Two 45o triangles provide an easy method for plotting position and course and doing other chart work. Using protractor scales, the triangle is easily aligned in any direction with a chart meridian. Direction is maintained as one triangle is slid along the other to the desired position. Durable, clear, vinylite. Long side length 30 cm.