Search new + high quality used tires online. Size 305 30 R21 starting at: $47.99. Tires in stock: 44. Available brands: 3 with 5 models. All season: 8. Summer: 36.. 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!