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Weems and Plath Paralock Plotter

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The Weems and Plath Paralock Plotter is a parallel ruler of compact size (less than half the length of a standard model) that will be found especially applicable for use on modern smaller chart tables.


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Weems and Plath Paralock Plotter

The Weems and Plath Paralock Plotter is a parallel ruler of compact size (less than half the length of a standard model) that will be found especially applicable for use on modern smaller chart tables.

The primary purpose of the Weems and Plath Paralock Plotter is to enable the transfer of GPS positions rapidly, easily and accurately to and from any paper chart.

It features three unique design details:

  • A locking knob that allows the user to quickly plot a GPS position on paper charts
  • Two sets of finger holes that enable finger tips to act as friction pads on the underlying chart
  • Opening to the same width as conventional rules although shorter than standard size rules and therefore covering the same chart area

The most innovative feature of this patented device is the locking knob located at one of the four pivot points of the ruler’s cross–arms. This knob enables the two rulers to be fixed in any given separation which allows rapid determination of GPS position.

The Weems and Plath Paralock Plotter is only 7.25 inches long as opposed to the standard rule length of 15 inches, but its opening width is the same as standard rules.

Placing fingertips in the twin finger holes allows easy operation of the rule and readily informs the operator if a slip has accidentally occurred while aboard a rolling or pitching vessel.

The Weems and Plath Paralock Plotter is made of sturdy, clear acrylic for maximum chart visibility. It has graduations so it can be used as a protractor to determine a compass bearing and it also has a ruler across the bottom, making it is easy to take distances and transfer them to a mileage scale.

This plotter has all the features of a standard parallel rule but it fits in a pocket and is easier to use.

The Paralock Plotter is perfect for any boater who keeps track of latitude and longitude coordinates on a paper chart. Its compact, convenient size also makes it the right tool for use on boats with limited chart space.

  • Length: 7 1/4 inches (184 mm)
  • Weight: 0.21 lb (95 g)