
Weems & Plath ParaLock Plotter
The Weems & Plath ParaLock Plotter is a compact and innovative parallel rule designed specifically for transferring GPS positions to and from paper charts.
This unique plotter features a locking knob that allows you to quickly and accurately determine latitude and longitude coordinates. Its compact size makes it ideal for use on small chart tables or in confined spaces, while its clever design ensures precise and efficient chartwork.
Features:
- 7-1/4 inches (18.42cm) long
- Sturdy, clear acrylic for maximum chart visibility
- Locking knob for fixing the rule opening
- Finger holes for enhanced grip and control
- Graduations for use as a protractor
- Ruler across the bottom for measuring distances
- Fits in a pocket or drawer
- Plastic storage sleeve with instructions
- Limited Lifetime Warranty
How to Use the ParaLock Plotter
To transfer a GPS position to a chart, place one edge of the plotter at the latitude coordinate on the chart's scale. Open the device until the other edge aligns with the nearest parallel of latitude. Lock the plotter using the knob and slide it along the parallel of latitude until it reaches the approximate longitude coordinate. Repeat the process using a meridian line to determine the precise position.
A Modern Twist on a Classic Tool
The ParaLock Plotter combines the functionality of a traditional parallel rule with innovative features designed for modern navigation. Its compact size, locking knob, and finger holes make it a versatile and efficient tool for any navigator who works with paper charts and GPS coordinates.
About Weems & Plath
Founded in 1928 by Lieutenant Commander Philip Van Horn Weems, Weems & Plath has a long and distinguished history of providing sailors with high-quality nautical instruments and navigational tools. From the Weems Plotter to the Second Setting Watch, their innovations have helped shape the world of navigation.
Today, Weems & Plath continues to uphold its tradition of craftsmanship and precision, offering a wide range of navigational tools and instruments for sailors of all levels.
Original: $40.07
-70%$40.07
$12.02More Images

Weems & Plath ParaLock Plotter
The Weems & Plath ParaLock Plotter is a compact and innovative parallel rule designed specifically for transferring GPS positions to and from paper charts.
This unique plotter features a locking knob that allows you to quickly and accurately determine latitude and longitude coordinates. Its compact size makes it ideal for use on small chart tables or in confined spaces, while its clever design ensures precise and efficient chartwork.
Features:
- 7-1/4 inches (18.42cm) long
- Sturdy, clear acrylic for maximum chart visibility
- Locking knob for fixing the rule opening
- Finger holes for enhanced grip and control
- Graduations for use as a protractor
- Ruler across the bottom for measuring distances
- Fits in a pocket or drawer
- Plastic storage sleeve with instructions
- Limited Lifetime Warranty
How to Use the ParaLock Plotter
To transfer a GPS position to a chart, place one edge of the plotter at the latitude coordinate on the chart's scale. Open the device until the other edge aligns with the nearest parallel of latitude. Lock the plotter using the knob and slide it along the parallel of latitude until it reaches the approximate longitude coordinate. Repeat the process using a meridian line to determine the precise position.
A Modern Twist on a Classic Tool
The ParaLock Plotter combines the functionality of a traditional parallel rule with innovative features designed for modern navigation. Its compact size, locking knob, and finger holes make it a versatile and efficient tool for any navigator who works with paper charts and GPS coordinates.
About Weems & Plath
Founded in 1928 by Lieutenant Commander Philip Van Horn Weems, Weems & Plath has a long and distinguished history of providing sailors with high-quality nautical instruments and navigational tools. From the Weems Plotter to the Second Setting Watch, their innovations have helped shape the world of navigation.
Today, Weems & Plath continues to uphold its tradition of craftsmanship and precision, offering a wide range of navigational tools and instruments for sailors of all levels.
Product Information
Product Information
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Shipping & Returns
Description
The Weems & Plath ParaLock Plotter is a compact and innovative parallel rule designed specifically for transferring GPS positions to and from paper charts.
This unique plotter features a locking knob that allows you to quickly and accurately determine latitude and longitude coordinates. Its compact size makes it ideal for use on small chart tables or in confined spaces, while its clever design ensures precise and efficient chartwork.
Features:
- 7-1/4 inches (18.42cm) long
- Sturdy, clear acrylic for maximum chart visibility
- Locking knob for fixing the rule opening
- Finger holes for enhanced grip and control
- Graduations for use as a protractor
- Ruler across the bottom for measuring distances
- Fits in a pocket or drawer
- Plastic storage sleeve with instructions
- Limited Lifetime Warranty
How to Use the ParaLock Plotter
To transfer a GPS position to a chart, place one edge of the plotter at the latitude coordinate on the chart's scale. Open the device until the other edge aligns with the nearest parallel of latitude. Lock the plotter using the knob and slide it along the parallel of latitude until it reaches the approximate longitude coordinate. Repeat the process using a meridian line to determine the precise position.
A Modern Twist on a Classic Tool
The ParaLock Plotter combines the functionality of a traditional parallel rule with innovative features designed for modern navigation. Its compact size, locking knob, and finger holes make it a versatile and efficient tool for any navigator who works with paper charts and GPS coordinates.
About Weems & Plath
Founded in 1928 by Lieutenant Commander Philip Van Horn Weems, Weems & Plath has a long and distinguished history of providing sailors with high-quality nautical instruments and navigational tools. From the Weems Plotter to the Second Setting Watch, their innovations have helped shape the world of navigation.
Today, Weems & Plath continues to uphold its tradition of craftsmanship and precision, offering a wide range of navigational tools and instruments for sailors of all levels.














