Cobra build their competition shells in two widths and their road, reclining and classic ranges in one. Get the width name right and the model choice mostly follows.
How Cobra size their seats
The composite competition shells (Sebring, Suzuka, Imola, Evolution) come as Standard, which we list for a 28 to 32 inch waist, and GT, for 32 to 36. Cobra list the same external dimensions for both, so the difference is in the fit through the hips and shoulders: go by the waist band, not the drawing. The steel-framed Monaco follows the same idea with a Standard, a 32 to 36 and a Monaco GT for 36 to 38.
The reclining Misano, Daytona, Le Mans and Stuttgart are one size each and take a 32 to 38 inch waist. The classic range (Clubman, Cub, Roadster, RS, Interlagos, the Classic itself) is one size and suits most drivers; the exceptions are noted in the table.
Over 6 ftThe Sebring and Nogaro shells are the tall ones, 910 to 935 mm high with the head support set for a long body. The Suzuka Standard, the Monaco and most of the classics suit drivers under 6 ft better.
Which Cobra fits you
Cobra dimensions
Cobra publish overall height, width, depth and base width for most shells. All figures in mm, weight in kg where Cobra give one.
Width is the widest point of the shell, usually across the shoulder wings on a bucket and across the bolsters on a recliner. Base width is what has to clear the tunnel and the door card.
Measure yourself first
Four numbers decide whether a seat fits. Take them in the clothes you drive in, and write them down before you compare models.
AWaistAround your natural waist, not your trouser size. Trouser sizes usually run an inch or two under the real figure, and the waist bands on our product pages use the real one.
BSeated hip widthSit on a hard chair with your feet flat and measure straight across the widest point of your hips with a rule or a straight edge, not a tape that follows the curve. This is the number that decides whether a fixed shell is tight.
CShouldersStraight across the back at the widest point. Fixed back seats hold you here, so a shell that is narrow at the shoulders is uncomfortable long before it is unsafe.
DHeight and torsoYour height, and if you are over 6 ft whether that is mostly leg or mostly body. A long body needs a taller shell with the head support set higher.
Before you order
- Check the car, not only the driver. Transmission tunnels, door cards and B pillars are what stop a wide shell going in. Our seat mounting and fixing points guide covers what to measure.
- Side mount and base mount shells are not interchangeable. Which one you need depends on the car and the subframe, so pick the brackets at the same time as the seat.
- If you run a HANS or plan to, filter on HANS friendly. The shoulder openings are cut to clear the collar.
- FIA seats carry an expiry date on the homologation label. Check what your championship accepts and how long the seat has left, particularly on discounted older stock.
Send us your measurementsWaist, seated hip width, height and the car. We have fitted a lot of Cobra seats and will tell you honestly if the one you have picked is going to be tight. Call 0115 989 3488 or email Sales@GSMPerformance.co.uk.
Waist bands and heights are our product data, checked 6 September 2026. Dimensions are Cobra’s own published figures as carried on our product pages.