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Eco Contact 7 S

235/40R21 H (98)
4.4/5
(8 reviews)
  • C
    Fuel Efficiency
    Fuel Efficiency / Rolling Resistance: C

    How much fuel the tyre uses as it rolls. Graded A to E, where A is the most efficient and E the least.

  • A
    Wet Grip
    Wet Grip / Braking Performance: A

    How well the tyre stops in the wet. Graded A to E, where A is the shortest stopping distance. Each grade is worth roughly 3 metres, about a car length.

  • B72 dB
    External Noise
    Noise Emission / Exterior Noise: B (72 dB)

    How loud the tyre is from outside the car, measured in decibels. Graded A to C, where A is the quietest.

Wet Grip Excellence
  • Tick Icon Car
    Car tyre:

    Designed for cars, rather than vans, 4x4s or commercial vehicles.

  • Tick Icon Reinforced (XL)
    Extra Load or Reinforced tyres:

    A stronger sidewall lets this tyre carry more weight than a standard tyre of the same size. Marked XL on the sidewall.

Fit from:03-09-2026
Fully Fitted Price
£26215
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235/40 R21 Dimensions Explained

235/40 R21 is a low-profile tyre for cars with 21-inch wheels. The first number represents width. So 235 means the tyre is 235mm wide. 40 is the sidewall height in relation to the width, so with 40, the height is 40% of the width (235) which is 94mm. R21 means a radial tyre for a 21-inch rim with an overall diameter of 721mm. At Tyres.co.uk, we have 235/40 R21, including the XL versions.

Part of the sizeValueWhat it means
Section width 235 The width of the tyre across the tread, measured in millimetres.
Profile (aspect ratio) 40 Sidewall height as a percentage of the width - here, 40% of 235 mm (about 94 mm).
Construction R Radial construction, which is what nearly all road tyres use.
Rim diameter 21 The wheel diameter the tyre fits, measured in inches.
Your tyre dimensions
MeasurementValue
Sidewall height 94.0 mm (3.70 in)
Overall diameter 721 mm (28.4 in)
Circumference 2,266 mm (89.2 in)
Revolutions 710 per mile · 441 per km
Equivalent sizes
SizeOverall diameter
235/45 R20 720 mm · -0.3%
245/45 R20 728 mm · +1.0%
245/40 R21 729 mm · +1.1%
255/40 R20 712 mm · -1.3%
255/35 R21 712 mm · -1.3%
255/30 R22 712 mm · -1.3%