Tillett Tb3 Side Mount Bracket TBB5T (OLD VERSION WAS TB3) Side Mounts For B5 £153.60 Incl. VAT£128.00 Excl. VAT
Recaro FIA Sliding Side Mount Recaro FIA Approved Sliding Seat Mount From £787.50 Incl. VATFrom £656.25 Excl. VAT

Tillett STRI (FORMERLY TR1) Adjustable Seat Runner Set

£138.91 Excl. VAT

Tillett Stri Adjustable Seat Runner Set by Tillett Seats. Brand: Tillett Seats. Compatible Seats: Tillett B8, Tillett B9. Available now from stock.

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The Tillett STRI, sold under the original code TR1, is an adjustable seat runner set for the Tillett B8 and B9. SKU TR1. It is the component that sits between the seat shell and the fitting frame, letting you slide the seat forward and back to find your driving position before locking it in place.

The STRI is designed for inward-pointing bracket configurations. Tillett produce two runner types: the STRI (inward) and the STRO (outward, formerly TR2). These are not interchangeable. If your fitting frame uses outward-pointing brackets, the STRO is the correct product. Check your bracket angle before ordering.

Compatibility is confirmed for the B8 and B9. If you are fitting a B6 or W1i, the runner adapter kit listed separately is the relevant product for that seat.

Tillett runners are machined to work within their own bracket system. The runner width and locking mechanism are designed to the same tolerances as the rest of the Tillett fitting range, which is why Tillett specify their own runners rather than leaving it open to aftermarket options.

If you are building a car where the seat will come out regularly between events, or where position needs to repeat reliably session to session, a proper runner set is worth fitting properly. Estimating the position by re-bolting the seat direct each time introduces error that a runner set removes.

Weight 1.38 kg
Brand

Compatible Seats

,

In-store displays:

We have a premium range of over 125 seats from brands including: Bimarco, Cobra, Corbeau, Sparco, OMP, Recaro, GP-Race, and Bride to name just a few brands we work with.  

Alongside this, we also stock and display HANS devices, harnesses, race-wear, race-suits, FIA helmets and various other safety equipment. If you are looking to visit us to see and try any particular seat or product, please contact us in advance and we’ll be happy to help.

In-Store appointments:

Book now!

Due to the specialist nature of our services, we do ask that you please contact us in advance to book an appointment. We have multiple slots available each day including selected availability at the weekend.

Working by appointment allows us to dedicate our time with you and provide a personal and professional service. We’ll always ensure you leave with the right equipment for your needs.

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Fast delivery lead times:

If you require fast delivery, please contact us in advance of ordering and we’ll happily check stock allocation and availability for you. We carry a large amount of stock at our showroom and across multiple distribution hubs. This allows us to provide immediate dispatch across a huge number of brands from Corbeau and Cobra through to Sparco and OMP. (Does not apply to all items)

Due to the niche market we work in, some products are custom hand made to order, or special order from manufacturers like PCI Racing and Planted Technology. If you want to know how fast a product will be dispatched. Simply drop us a message through our Contact us form.

ParcelForce

Addtional lead time notes:

Quick dispatch: Stocked products are dispatched within 24-48 hours with Parcel Force.
Sparco roll cages: We can only deliver these to a registered (LTD) company address.
In-store collection: Please contact us in advance to book an in-store collection appointment.

Availability

Tillett seats are custom-made to order due to the specialist nature of the products. These stunning Carbon seats are handcrafted here in the UK. We do not currently stock or display them in our shop as they are special order items.

Current lead times: Tillett seats are currently average delivery times of 8-14 weeks due to hand demand and production capacity. Dispatch times vary and will depend on constantly rotating stock. Please contact us for precise lead times prior to order.

Need them fast?  Please contact us in advance to check our stock and product availability. If we have excess stock of some models, we may be able to dispatch them within a shorter lead time. Speak to us in advance to find out how we can assist.

Tillett B2 Carbon Epoxy Racing Car Seat

Seat runner and slider guide

Sliding runners let you move a fixed back bucket seat forwards and backwards. There is one thing everybody gets wrong about them, and it is worth clearing up before you look at the range.

The millimetres are the handle width, not the travelA 405 mm runner does not move further than a 291 mm runner. Every runner here gives the same fore and aft adjustment. The figure in the title is the width of the handle bar that spans underneath the seat, and you pick it to match the width of the shell you are fitting. All three Corbeau options are the same price, which is the giveaway.

Match the handle width to the seat

Measure across the underside of your seat between the two mounting rails, or check the seat width the manufacturer quotes. Then pick the runner whose handle spans it.

Handle width Sold as What it suits
290 mm Retro and Sportline Narrow shells and classic seats
291 mm Cobra, Corbeau The common narrow option
320 mm Motorsport STD Standard width bucket seats
345 mm Corbeau A step up from standard
370 mm Motorsport L Wider shells
405 mm Motorsport XL, Cobra, Corbeau The widest we stock

If you are between two, go by the seat rather than by preference. A handle that is too narrow will not reach the rails and one that is too wide will foul the tunnel or the sill.

Runners made for a specific seat

Some kits are built for one shell rather than sold by width. If your seat is on this list, that kit is the easier answer.

Brand Seats Notes
Tillett B5, B8, B9 Runner kits made for those shells
Recaro Pro Racer SPA and SPG, standard and XL Two widths, matched to the shell
Sparco P1300GT and P1300GT LW Base mount kit, quotes a seat width
Cobra Nogaro Sliding fitting kit for that seat
Endurance Sparco and Recaro compatible Aftermarket kits to suit those shells
Check the fixing type firstThe Sparco and Endurance runner kits are written for base mounted seats and quote a seat width rather than a handle width. A side mount seat needs side mounts and a subframe, not a base runner. Read our seat mounting and fixing points guide if you are not sure which yours is.

What a runner costs you

Height

A runner sits between the seat and the subframe, so it lifts you. In a car with a cage and a helmet that is the first thing to check, because the few centimetres it adds is exactly the amount you did not have spare. If you are tall, work out your headroom before you commit to running sliders at all.

Rigidity

A fixed seat bolted straight to a subframe is the stiffest way to mount it. A runner adds a moving joint. It is entirely normal for road and track day use, and it is why a lot of competition cars do without.

Sharing the car

The obvious reason to fit them. If two drivers use the car, or you drive it to the circuit and someone else drives it home, runners are worth the height and the weight. If it is your car and only yours, bolting the seat where you want it is simpler and lower.

Tell us the seat and we will match the runnerThe seat make and model, and whether it is side mount or base mount. The handle width has to match the shell and it is quicker for us to check than for you to measure it twice. Call 0115 989 3488 or email Sales@GSMPerformance.co.uk.

Widths and compatibility read from our own product data, checked 2 August 2026. All runners in this range give the same fore and aft adjustment.

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