TSO Products

GRS-16 Guide Rail Square

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  • Break down sheet goods with unmatched speed and accuracy with your track saw.
  • The GRS-16 Guide Rail Square is the easiest, fastest and most accurate way to square cuts with your Festool, Makita or Triton track saw.
  • Compatible with Festool, Makita and Powertec brand guide rails.
  • Your guide rail is completely supported by the full-height, precision machined recess of the GRS-16.
  • Simply slide the GRS-16 into your guide rail t-track, clamp down the draw latch, and you're ready to get to work.
  • The high strength draw latch features a comfort coating, making it easy to engage.
  • Once attached to your guide rail, slide the front edge of the GRS-16 up to your workpiece and cut away.
  • A special dipped coating on the latch protects your guide rail.
  • Perfectly balanced once attached to your guide rail, so it can easily hang off the front edge of your workpiece.
  • The GRS-16 is designed to not interfere with your track saw, even when fully plunged.
  • Compatible with Makita and Powertec tracks as well.
  • Integrated clamping slot enables use of Festool's screw or rapid clamps.
  • Use in combination with a GRS-16 PE (sold separately) to square both ends of your workpiece at once.
  • Extend your guide rail square's effective reference edge thickness and length with our optional Angle Accessory.
  • Connects to the TSO Parallel Guide System (sold separately) to enable fast, square, parallel and repeatable cuts!
  • Use the GRS-16 in place of a Guide Rail Adapter with the TSO Parallel Guide System.
  • Store and protect your GRS-16 on the go, with our Foam Insert and TSO Systainer3 (sold separately).
  • With our optional Dual Foam Insert Set, the GRS-16 and GRS-16 PE both fit in a single Systainer!
  • GRS-16 Guide Rail Square
  • GRS-16 Guide Rail Square


Original, Patented Guide Rail Square for FESTOOL®, MAKITA®, Milwaukee®, POWERTEC® & TRITON®

Introducing the newest version of the best-selling guide rail square on the market: the GRS-16. Incorporating a number of user-driven enhancements, the TSO GRS-16 guide rail square is still the fastest, easiest and most accurate way to square cuts with your FESTOOL, MAKITA, MILWAUKEE, POWERTEC and TRITON track saw guide rails.

Featuring New Enhancements

Thanks to feedback from the TSO user community, the GRS-16 guide rail square now includes:

  • Our lightest design ever despite being CNC machined from 25% thicker aluminum, with a mating vertical edge providing maximum guide rail support
  • Latch hook resilient coating grasps and protects the edge of your guide rail
  • Easier to install onto your guide rail with a reshaped T-feature lead-in
  • Accessory mounting holes tapped for M6 threads—enables connection to the TSO Parallel Guide System and Angle Accessory
  • Available Dual FoamPac Systainer Insert fits both the GRS-16 and GRS-16 PE in a single Systainer
  • New, fully recyclable all-corrugated white packaging

See How It Works

Simple, Automatic Accuracy

Introducing the fastest way to dead square cuts with your track saw: the GRS-16 Guide Rail Square. With its custom-made and powerful draw latch, the GRS-16 instantly self-squares while it clamps down to your track. And with a one-piece design made from a solid chunk of CNC-milled aluminum, you won't have to worry about losing that screw, clamp or other necessary accessory. Simply slide the GRS-16 onto your guide rail, clamp it down, and get to work.

Compatible with guide rail clamps

Accurate cuts with your track saw may require using a screw or quick clamp to secure the guide rail to your workpiece. For this reason, the GRS-16 features notches to accommodate popular clamps from Festool, Axminster, or the like.

Built to be a Lifetime Tool

The GRS-16 is precision CNC machined from a single piece of 5/8" (15 mm) thick 6061-T6 aluminum and then anodized for a non-marring, high durability finish. The high-strength draw latch is custom-made from stainless steel to resist rust and pitting over time. Despite its high clamping strength, a comfort coating on the latch handle makes it easy to generate the leverage necessary to engage, release or reposition the square along your length of track. The GRS-16 guide rail square is made in the United States, and comes with our five-year warranty.

So Which Tool is Right for You?

If you want the absolute smallest and lightest form factor and anticipate using the square for conventional cuts referencing the front edge of your workpiece, choose the GRS-16 (the product you see on this page). If you need the ability to reference off the front and back edge of your workpiece, select the GRS-16 PE.

Connect your GRS-16 to the TSO Parallel Guide System

A System Approach

The GRS-16 is much more than a guide rail square; in fact, it's the foundation of a broader system of TSO Products designed for interoperability. Case in point: the GRS-16 includes attachment points to connect to the TSO Parallel Guide System. Once connected, you can repeatedly square and parallel rip multiple workpieces in a single operation.

Technical Details

  • Dimensions: 15.2 x 6.0 x 1.4 inches (385 x 152 x 36 mm)
  • Weight: 1.7 lbs (772 g)
  • Material: 6061-T6 aluminum, anodized, 5/8 in (15 mm) thick
  • Compatible Guide Rails (Both): Festool, Makita, Powertec, and Triton (not compatible with Festool HK 55 Carpentry Saws including the FSK 250, FSK 420 and FSK 670; not compatible with Bosch or DeWalt tracks)
  • Clamping Mechanism: Over center draw latch (304 stainless steel) with compensating spring; secured with M4x0.7-10 stainless steel socket head screws
  • Accessory Mounting Holes: Tapped for M6 threads for compatibility with TSO Parallel Guide System and Angle Accessory



Quick video walkthrough of the original GRS-16.

Special thanks to Eric at The Poplar Shop for his unexpected video review of the original GRS-16!

Guide Rail Square Comparison Table

Guide Rail Square
Guide Rail Square
  GRS-16 GRS-16 PE
Best for… Squaring your guide rail by referencing off the front edge of your workpiece Squaring your guide rail by referencing off either the front or back edge of your workpiece
Price $179.95 $189.95
Optional Add-ons TSO Parallel Guide System
TSO Limited Edition Systainer³ M 112
FoamPack Storage Insert for T-LOC Systainer & Systainer³ M 112
Angle Accessory
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Warranty & Returns

TSO brand products are guaranteed for five years from date of sale against defects in materials or workmanship. Normal wear and tear and accidental damage are not covered. For any product determined to have a defect covered by this warranty, TSO Products will repair or, at its option, replace with current comparable product. Warranty requests require an RMA (return authorization number) prior to any return. Request an RMA number by contacting TSO Customer Service (
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193 Reviews

  • 5

    Posted by Brian Dunphy on 15th Mar 2024

    I bought the TSO GRS-16 Guide Rail Square to complete my recent purchase of my Makita Track Saw and Powertec track and couldn’t be happier. The quality of the TSO GRS-16 Guide Rail Square is unrivaled in my opinion. I received my product very quickly and without any issues. I highly recommend this product.

  • 5

    Posted by John mitchell Sr. on 15th Feb 2024

    VERY percise

  • 5
    Perfect 90 degrees with Festool Track Saw

    Posted by Jim B on 21st Dec 2023

    I'm new to cabinet making and needed to break down 4 sheets of plywood for my first cabinets. Using both a Festool track saw and the TSO GRS-16 Guide Rail Square, everything came together perfectly. An absolute necessary accessory to go along with your track saw.

  • 5
    Guide rail squares - perfect

    Posted by Nis on 15th Dec 2023

    I don’t know how I’d live without these guide rail squares. When ripping a 4x8 sheet of plywood I attach the GRS-16 on one end and my GRS-16PE on the other end of my guide rail and get perfect cuts. Who needs a table saw if you have these? Not me. Highly recommended.

  • 5
    GRS 16 Guide Rail Square

    Posted by Thomas M. O'Keefe on 23rd Aug 2023

    Does everything it’s supposed to do. Version 2 has some advantages, but the original meets all my requirements.

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