Metzeler TIRE Z8-O 180/55ZR17 73W Size: 180/55ZR-17 "O SPEC" Style: REAR Color: BLACK Warranty: Tires that have manufacturing or material anomalies are covered under the warranty. Out of round, lateral or radial run out of more than 1.3 mm from center line, and out of balance (more than 2.8 ounces (80 grams) on most tires, 3.5 ounces (100 grams) on larger-sized touring tires) are examples of justified warranty claims. Claims for non-uniformity or any ride related condition will be accepted within the first 0.5 mm of tread wear.