Brand: American Roadstar Model: Sport A/S Size: 315-30R21 315/30-21 315/30R21 315/30/21 315-30-21 315 30 21 3153021 Tread Depth: 10/32 Treadlife: 50,000 miles Season: All Season Performance: High Performance Car Type: Truck/SUV Load and Speed Rating: 105Y Speed Rating Description: Speed Rated Up to 186 mph Section Width: 315 Aspect Ratio: 30 Rim Diameter: 21 Production Year (DOT): N/A