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Key Markings Explained

• XL (Extra Load): Signifies a reinforced structure to handle heavier SUV weights.
• MFS: Maximum Flange Shield, an integrated rim protection feature.
• N0: Porsche Original Equipment approval, indicating a custom-tuned tyre for specific Porsche models. 

Popular Compatible Vehicles

Here are popular vehicles compatible with the 21" Bridgestone Dueler H/P Sport tyre range in the Irish market:

• Porsche Cayenne: Compatible with the "N0" marked sizes, typically in staggered setups (e.g., 285/40 R21 front and 315/35 R21 rear).
• Audi Q7 / Q8: Uses the 285/40 R21 size.
• BMW X5 / X6: Compatible with the 285/40 R21 and 315/35 R21 sizes in staggered fitments.
• Mercedes-Benz GLE / GLS: Can utilize the 285/40 R21 and 315/35 R21 sizes. 

Summer tyres are most common in Ireland, offering peak fuel efficiency mileage and grip when temperatures stay above 7°C. However, they are not the official standard for winter safety. Motorists must show caution in cold conditions; below 7°C, summer rubber hardens, significantly compromising grip and wet braking performance on cold, saturated Irish roads.

All-Season tyres are the superior "fit-and-forget" solution for Ireland's wet, temperate climate. Specifically engineered to remain flexible in the cold, they provide shorter stopping distances on near-freezing, rain-soaked surfaces and carry the 3PMSF certification for frost and light snow. They offer total year-round peace of mind without the hassle of seasonal swaps.

Load Rating: Maximum Weight Capacity Explained

The load index is a numerical code representing the maximum weight in kgs that a single tyre can safely carry. To ensure safety, the combined capacity of all four tyres must exceed the vehicle’s total weight when fully loaded.

Speed Rating: Maximum Velocity Explained

Represented by a letter, the speed rating indicates the maximum kph a tyre can maintain over a prolonged period. Higher speed ratings are engineered to handle the heat and stresses generated at faster speeds more effectively.

Quick Reference Guide

• Check your requirements: You can find the specific requirements for your vehicle on the tyre information plate (usually located on the driver-side door pillar) or in the owner's manual.
• Replacement rule: It is vital never to fit a tyre with a lower load index or speed rating than those recommended by the manufacturer.
• Common Ratings: Standard ratings include T (190 kph), H (210 kph), and V (240 kph). You can view a full conversion table below..

Available 21" CUV/SUV Sizes and Markings (Smallest to Largest)

• 285, 40, 21, 109Y, XL
• 285, 40, 21, 109Y, XL, N0 (Porsche)
• 315, 35, 21, 111Y, XL
• 315, 35, 21, 111Y, XL, N0 (Porsche), MFS