Brand: Armstrong Model: Tru-Trac SU Size: 275-50R21 275/50-21 275/50R21 275/50/21 275-50-21 275 50 21 2755021 Tread Depth: 9/32 Treadlife: 65,000 miles Season: All Season Performance: Performance Car Type: Truck/SUV Load and Speed Rating: 113V Speed Rating Description: Speed Rated Up to 149 mph Section Width: 275 Aspect Ratio: 50 Rim Diameter: 21 Production Year (DOT): N/A