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14" Bi-Rola Rule

Weems & Plath


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.


Adjustable radial arm allows automatic compass corrections in course plotting. Roller body with protractor markings and nautical mile scale. Radial arm has Loran interpolator scales and 200 millimeter rule. When radial arm and body are used jointly, the Bi-Rola becomes a 17in. divider. Speed/ time/ distance table included. Easy to following instructions included. Packaged in protective, durable vinyl pouch. Lifetime warranty.


  • Unique radial arm
  • .7" divider when radial arm and body are used together

Category: weems and platch

Type: Plotting Tool

Vendor: Weems & Plath