The 18" Aluminum Arm Parallel Ruler features aluminum arms and handles. The parallel ruler is manufactured to a 6mm thickness and 45 length. The high-quality construction of the parallel ruler is backed with a lifetime warranty.

An essential item in any proper navigation kit, the aluminum arm parallel ruler is used to plot direction on your nautical chart. The parallel ruler is, essentially, comprised of two straight-edges hinged so that they maintain the same angle. By alternating the moving edge, and securely holding down the non-moving edge, you can move the parallel ruler about the chart while still maintaining the same angle.

Weems & Plath item no. 138

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