Search new + high quality used tires online. Size 305 30 R21 starting at: $33.65. Tires in stock: 38. Available brands: 7 with 13 models. All season: 4. Winter: 1. Summer: 33.. 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!