Weems & Plath 155 14" Bi-Rola Rule

Weems & Plath 155 Bi-Rola Rule

The Bi-rola Rule is a rugged plotter that is used by professional navigators because it is quick and easy to use. Patented vertical and horizontal rolling motion simplifies course and plotting calculations. •Unique radial arm allows you to automatically include compass corrections in course plotting

•Roller body has protractor markings and nautical mile scale
•Radial arm has Loran interpolator scales and 200 milimeter rule
•When radial arm and body are used jointly, the bi-rola rule becomes a 17 inch (440mm) divider
•Speed/time/distance table included
•Protective, durable vinyl pouch included
•Easy to follow instructions included