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The RSA300 Fixed LE Rafter Square is a large, 300mm precision square with integrated spirit level. With enhanced features, we've created it to be top of its class when it comes to design, build quality, usability and style. As the bigger brother to the RSA180 Fixed LE, it's ideal if you work with big timber.

Developed for quick and simple marking/laying out of roof trusses and other carpentry tasks, made simpler and quicker thanks to a handy spirit level vial in the fence. It's smart and built to last with a range of features to ensure longevity when used day in day out onsite.

There are curved scribe notches throughout the length of the tool that relate to many common timber sizes. These can be used with a variety of marking tools such as carpenters pencils, automatic construction pencils or just a standard pencil. These also include thirds for marking rafter cuts. 

The RSA300 Fixed is manufactured in-house from the highest quality European T6 4mm thick aluminium. We CNC machine each tool to tight tolerances, with right angle precision of +/- 0.008° along the entire length. 

The ruler gauges are laser marked inside shallow recessed pockets that prevent them coming into contact with workpieces when laid flat. The white marks are clearly visible on the anti-glare blue anodised surface making outside reading easy.

The protective anodised seal also helps prevent corrosion and extend tool life. 

The fence has a handy spirit level calibrated to the top and bottom visible from all four sides. Really handy for checking the roof pitch or stairs for example.

The two part silver anodised aluminium fence is also CNC machined and is fixed to the tool via 8 stainless steel machine head bolts. This houses a 30mm spirit level with an accuracy of 48' 2mm making it perfect for marking and finding level marks when roofing and timber framing.

There are several features and marking gauges on the face of the tool, including;

  • 300mm rule (plus a smaller rule along the fence edge)
  • CNC deep engraved protractor gauge along the hypotenuse edge
  • Common rafter and hip/valley rafter gauges in degrees
  • Curved Scribe lines for common timber dimensions
  • 1/3rd scribe marks for common timber thicknesses
  • Rise per metre of run table
  • Rafter length per metre of run table

The precision and workmanship from our manufacturing process is unrivalled and next level compared to mass produced, laser cut or cast rafter squares. The RSA300 Fixed is built to an extremely high standard, made for tradespeople who are looking for exceptional durability, design and quality from their tools. 

  • Constructed from high quality 4mm aluminium
  • High precision CNC machine profiled
  • CNC machined aluminium fence
  • Handy 30mm spirit level in fence
  • Anodised protective finish
  • CNC laser marked graduation scales
  • CNC deep engraved protractor scale
  • Made in Great Britain
*Our tools are all small batch made and the anodising dye a natural product. As such, slight differences in the shade of blue can occur between batches.