Product Description
GRS-16 PE v2: Parallel Edge Guide Rail Square
The Original, Patented Guide Rail Square for FESTOOL®, MILWAUKEE®, MAKITA®, POWERTEC® & TRITON® Track Saws

Introducing the newest version of the best-selling guide rail square on the market: the GRS-16 PE v2. Designed to make it much faster to achieve dead square cuts with your track saw, the GRS-16 PE v2 improves upon the GRS-16 by adding a second "parallel edge" to permit squaring against the front and back of your workpiece.
Thanks to feedback from the TSO user community, we've continued to refine our original guide rail square design. What makes the GRS-16 PE v2 the best tool of its kind?
- NEW! Rapid attachment feature: simply insert the square at any point along the guide rail and clamp it in place—no need to slide it into the guide rail from one of the ends or remove hose deflectors, clamps, or other accessories occupying the guide rail T-slot
- NEW! A shallow undercut along the square's mating edge makes it less sensitive to minor dings and debris along the outer edge of the guide rail
- NEW! Now compatible with Milwaukee M18 FUEL™ 6-½" Plunge Track Saw guide rails.
- Single-piece design that self-squares to 90° with no adjustments needed (and therefore, no points of failure in the future)
- Lighter than its predecessor despite being CNC machined from 25% thicker aluminum, with a mating vertical edge that now perfectly matches the height of your guide rail extrusion for maximum support and engagement
- Draw latch hook now features a resilient coating to grasp your guide rail and protect it from marring
- Notches in both reference edges accommodate popular clamps like the Festool Screw Clamp (489570) and Quick Clamp (FS-HZ 160)
- Threaded M6 accessory mounting holes enable connection to the TSO Parallel Guide System and Angle Accessory
- Two squares fit in a Systainer—see our Systainer Foam Insert and limited edition TSO Blue Systainer3 M 112
- New, fully recyclable all-corrugated white packaging
See How It Works
Simple, Automatic Accuracy
Before the GRS-16, methods for squaring a track saw relied on the loose-tolerance T-slot found in every guide rail. To overcome this inherent inaccuracy, woodworkers relied on a separate reference square, plus a combination of loose parts like T-bars, hex bolts, and knobs. These shop-made solutions would often quickly fall out of square, requiring constant vigilance and recalibration to maintain accuracy.
The patented GRS-16 PE solves this problem with a simple one-piece design that self-squares as it attaches to the guide rail. Once the powerful draw latch is engaged, the GRS-16 PE becomes a rigid extension of your guide rail, providing two precise 90° reference edges that won’t fall out of square 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.
Made in the USA with a Five-Year Warranty
The GRS-16 PE is precision CNC machined from a single piece of 5/8" (15 mm) thick 6061-T6 aluminum and anodized for a non-marring, durable finish. The GRS-16 PE is made in Minneapolis, United States, and comes with an industry-leading five-year warranty.
GRS-16 or GRS-16 PE?
If you need the ability to reference off the front and back edge of your workpiece, select the GRS-16 PE. 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.
A System Approach
The GRS-16 PE is much more than a guide rail square; it's the foundation of a broader system of TSO Products designed for interoperability. In fact, the GRS-16 PE serves as a connection method for the TSO Parallel Guide System. Once connected, you can repeatedly square and parallel rip multiple workpieces.
Festool MFT/3 Compatibility
Did you know the GRS-16 PE can be connected directly to your MFT/3 guide rail hinge bracket? The time-consuming re-squaring process of the MFT guide rail is now a thing of the past. Rail squareness is now assured, unaffected by varying material thickness and rail height adjustment. The inspiration for this improvement came from customer Simon H., a Festool MFT/3 user in the UK. We listened and took action. Thank you, Simon!
We engineered this feature to keep the kerf line in exactly the same location as your standard MFT/3. You can quickly change back to the original MFT/3 arrangement any time.
GRS-16 PE connects perfect square to MFT/3
It does not get any more accurate than this!
Technical Details
- Dimensions: 15.2 x 6.0 x 1.4 inches (386 x 152 x 36 mm) - click here for dimension drawing
- Weight: 1.9 lbs (862 g)
- Material: 6061-T6 aluminum, anodized, 5/8 in (15 mm) thick
- Compatible Guide Rails: Fits FESTOOL, MILWAUKEE, 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. For KREG compatibility, see separate GRS-16 PE K model.
- 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
Videos
Quick video walkthrough of the original GRS-16 PE.
Special thanks to Eric at The Poplar Shop for his unexpected video review of the original GRS-16!
Guide Rail Square Comparison Table
GRS-16 Guide Rail Square | GRS-16 PE Guide Rail Square | |
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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 |
Got a suggestion to make this page even better? Your feedback and suggestions are always welcome!
Other Details
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 (info@tsoproducts.com).Product Videos
Videos Hide Videos Show Videos
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TSO Products GRS-16 Guide Rail Square. Quick review.
TSO Products sent me the GRS-16 guide rail square and asked me...
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New Release: GRS-16 Track Square
Damion Fauser, furniture designer/maker and Wood Review author...
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GRS-16 Track Saw Guide Rail Square Review
Looking for a quick and accurate way to make square cuts with ...
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One month review of my TSO Products GRS-16
I found thus company on the internet while searching for other...
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Testing the TSO GRS-16 PE Square with the FESTOOL FS1400 Guide Rail
The friendly people at TSO send me their TSO GRS-16 PE. I cut...
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GRS-16
An accessory tool for track saws that gives you perfect 90 deg...
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Track Saw Guide Rail Square - Presenting the GRS-16 PE
In just seconds, transform your Festool, Makita or Triton bran...
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Upgraded GRS-16 PE v2 Guide Rail Square with Faster, Drop-on Attachment
In just seconds, transform your Festool, Milwaukee, and Makita...
Custom Field
Product Reviews
207 Reviews Hide Reviews Show Reviews
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Awesome
Well built and great addition for track saw. Makes every cut on purchased plywood straight as an arrow.
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A great product
This is one of the beat things you can get to make a track saw go from good to great. Well-made and engineered to work easily and effectively.
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Absolutely amazing!
I love the GRS-16 PE, it is totally worth every cent! Accurate, easy to use.
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GRS-16 PE
Excellent quality. Easy on-off.
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GRS-16 PE
Extremely well made product. Works perfectly. Only thing lacking is a case to keep it safe in.
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Awesome addition to my Milwaukee Track Saw!
I know I could have spent less but I wanted to support US manufacturing and a US engineering & manufacturing company ... and I have to say that the quality is excellent as is the performance and accuracy of this Guide Rail Square. LOVE IT!
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Awesome tool
Has saved me from messing up a bunch of cuts. Would highly recommend
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Planing on using it a lot
Great idea and product
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GRS 16 PE
Great quality, fits snug and square, no slop or slippage.
We are continually striving to improve our products based on customer input. While we make every attempt to keep our product pages up-to-date, know that the product you receive may reflect recent improvements and therefore differ slightly from the product depicted. We reserve the right to change specification of products without notice.