The Limited Edition TrigJig RSA300 Adjustable Rafter Square is a large 300mm Rafter Square. 

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 Adjustable LE, it's ideal if you work with big timber. Developed for quick and simple marking/laying out of roof trusses with a smart adjustable fence that locks in position for speed, ease and repeatability. 

With several marking gauges on the tool's face, the RSA300 Adjustable can be used in many carpentry and fabrication projects, though its speciality is for roofing, timber framing and for use with large trusses and timber.

One  of our best rafter squares yet, the RSA300 Adjustable is manufactured in-house from the highest quality European aluminium. We CNC machine each tool to tight tolerances, with right angle precision of +/- 0.008° along the entire length. 

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. 

An anti-glare anodised surface and enlarged laser etched markings help with outdoor use. The laser marked graduation rulers and parallel scribe scales are recessed in pockets to avoid wear over time.

The degree lines are deep engraved so they won't rub off, and as they are made on the same CNC milling machine that profiles the square, the level of precision is excellent. 

The adjustable silver anodised aluminium fence is also CNC machined and is fixed to the tool via nylon 66 bearings for smooth operation that snaps back to exactly 0°. The fence can be locked in place with a stainless steel thumb screw for repeatable cuts and marking super precise birds mouths, without any repeat measuring required.

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

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

• Constructed from high quality T6 aluminium
• High precision CNC machine profiled
• Adjustable CNC machined aluminium fence
• Anodised protective finish
• CNC laser marked graduation scales
• Made in Great Britain

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 Adjustable LE is built to an extremely high standard, made for tradespeople who are looking for exceptional durability, design and quality from their tools. 

Lifetime warranty when registered within 30 days of purchase -read more

Delivery costs

UK £5.99 for orders up to £150, Free shipping over £150

All bladed items require Age Verification with ID on delivery, this is £6.99 to comply with the new law on shipping blades

All other countries - shipping is calculated at checkout based on your shipping address and weight of items in the basket.

Delivery Times

UK Delivery

All our shipping is sent Tracked to ensure you receive your goods securely and timely. If it is over a certain value we will send it Tracked with a Signature. We dispatch all orders within 1-2 working days.

We have recently switched to Royal Mail who offer 24hr Tracked & Signed delivery from Monday to Saturday. We can't offer time slots or weekday only deliveries as Royal Mail will deliver this on your usual post delivery.

We don't accept responsibility for delivery to building sites as we can't guarantee who will sign for it and unfortunately previous deliveries have gone missing due to this. If you choose to use a building site address and it is shown as delivered on tracking, we will not accept any liability if you were not the person who received it.

If you enter an incomplete address on your order and the order is returned to us, you will need to pay the outbound shipping cost for the second shipment of it to you.

International Delivery - the same terms apply but with a guideline delivery time of up to 1-2 weeks days depending on your country.

Delivery queries

All orders are sent on a Tracked service, we send tracking information on dispatch & tracking shows the live status of the delivery day. It is the customer responsibility to check tracking & ensure they are present for the delivery time. If the customer is not available, they can amend the delivery date to another day or collect from a local collection point. If the order is delivered on the stated delivery day stated when the customer is not present & after delivery the parcel is stolen this is not the responsibility of TF Tools Ltd.

Any issues with delivery of goods, damages, incorrectly sent items must be notified to us within 14 days, this is the customer's responsibility.

For damages - you need to take images of the damage to the item and/ or packaging to support the complaint with the courier and send to info@tftools.co.uk with your order number (starts TFT).

The items must remain unused, in original packaging and in resalable condition for us to provide a resolution.

If it is after 14 days or the items has been used, this will be considered acceptance of the goods as received.

Return to Sender - Royal Mail now charge for failed deliveries for incorrect delivery addresses, tracked parcels not collected, unpaid customs on international deliveries. TF Tools Ltd will charge a subsidized fee of £4.99 to partially cover this cost, this will be deducted from a refund or chargeable when resending the parcel plus the usual new shipping fee