Proxes ST III
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Specifications
| Size | 275/50R21 XL Proxes ST Iii |
|---|---|
| Width | 275 mm |
| Aspect ratio | 50 |
| Rim diameter | R21 |
| Load index | 113 |
| Speed rating | V |
| Load range | XL |
| Season | All-Season |
|---|---|
| Treadwear warranty | 40,000 miles |
| Tread depth | 10.1/32" |
| Weight | 41 lbs |
| Max pressure | 50 psi |
| Severe snow (3PMSF) | No |
| Run-flat | No |
About the Toyo Proxes ST III
All-Season High Performance Passenger Light Truck/SUV and Crossover tire.
Features
* Dynamic directional tread design* Directional shoulder blocks* Lightning grooves* Arrowhead tapers* Multi-wave sipes* 40,000 Mile/64,000 Kilometer Limited Treadwear Warranty* 500 Mile Trial Offer
Benefits
* Provides a good balance between wet traction, dry handling and performance based looks* Stabilizes tread blocks for better braking performance and a quieter ride* Enables better water evacuation resulting in better wet performance* Delivers tread block stiffness resulting in better straight-line driving stability* Maximizes irregular wear for a smooth, quiet ride and improves light snow traction
Understanding the 275/50R21 XL size
In the size code 275/50R21, 275 is the section width in millimetres (about 10.8"). 50 is the aspect ratio — the sidewall height is 50% of the width, or roughly 137.5 mm. R21 means radial construction on a 21-inch wheel, giving an approximate overall diameter of 31.8".
The load index 113 means each tire supports up to 2,535 lbs — about 10,140 lbs across a full set of four. The speed symbol V certifies the tire to 149 mph under its rated load. Always match or exceed the load index and speed rating listed on your vehicle's door-jamb placard.
What the Toyo Proxes ST III is built for
The Toyo Proxes ST III is an all-season tire, balancing dry grip, wet traction and tread life across spring, summer and autumn conditions. It carries an M+S (mud and snow) marking for light winter service. It is classified for highway terrain(h/t) use.
Price and value
At $173.71 per tire, a full set of four costs $694.84. That is about 40% below the average price of the 12 tires we stock in this size. Backed by a 40,000-mile treadwear warranty, that works out to roughly $17.37 per 1,000 miles across the set.
Frequently asked questions
What does the tire size 275/50R21 mean?
275 is the section width in millimetres, 50 is the aspect ratio (sidewall height as a percentage of width, about 137.5 mm), and R21 indicates radial construction for a 21-inch wheel. Overall diameter is approximately 31.8 inches.
What are the load and speed ratings of the Toyo Proxes ST III 275/50R21 XL?
Its load index of 113 allows up to 2,535 lbs per tire. Its speed rating of V is certified to 149 mph. Check your door-jamb placard and do not fit a tire rated below the vehicle's requirement.
How much does a set of 4 Toyo Proxes ST III 275/50R21 XL tires cost?
A single tire is $173.71 and a set of four is $694.84, covered by a 40,000-mile treadwear warranty.
Does the Proxes ST III come in other sizes?
Yes — we stock 50 additional Proxes ST III sizes besides 275/50R21 XL. Fit only a size approved for your vehicle.