Search new + high quality used tires online. Size 305 30 R21 starting at: $33.07. Tires in stock: 447. Available brands: 6 with 25 models. All season: 96. Winter: 4. Summer: 347.. Selling all used tires at discount costs. All used tires go through 2 layers of inspection on specialized equipment. One year warranty + free shipping on all inventory ;) Happy shopping!