This professional protractor triangle with handle is larger than other navigation triangles on the market, with legs that are 9.312 inches long and a hypotenuse (long side) 13.125 inches long. The protractor has both 320mm & 1-80,000 scales, and is manufactured from a clear, heavy-duty 5mm thick acrylic for durability. Pencil and pencil sharpener included. Lifetime warranty.

Dimensions:

33.3 x 23.5 x 0.47cm.

Directions For Use:

1. Slide two triangles to transfer course or bearing.
2. Place protractor vertex over meridian of longitude to determine course or bearing
3. Hole at the vertex of the protractor allows the point of the divider or pencil to be placed on meridian for a quick accurate course measurement
4. A string fixed through the hole can be used on a chart to determine a long distance course.
5. On shipboard, a string through the hole with a weight can be used to determine a long distance course.
6. Convert the protractor into quadrant to measure the altitude of Polaris to determine latitude at night. Use a string of fishing line tied to the vertex with a weight at the other end to determine the angle.
7. Measure angle/altitude of on shore object (tower/lighthouse) to determine distance from your location. Add the bearing for a fix.