215 55 zr17的意思

"215 55 R17" is a tire size designation, where:

• "215" refers to the tire's width in millimeters. This is the width of the tire from one sidewall to the other when it's mounted and ready to be used on a vehicle.
• "55" is the aspect ratio, which is the percentage of the tire's width that the tire's sidewall height is. In this case, the sidewall height is 55% of 215mm.
• "R" stands for "radial," which indicates the construction method of the tire. Most tires sold today are radial, meaning the layers run perpendicular to the direction of travel.
• "17" is the diameter of the wheel in inches that the tire is designed to fit. This is the size of the wheel's rim.

So, a tire size of 215/55R17 means that the tire has a width of 215 millimeters, a sidewall height that is 55% of the tire's width, a radial construction, and is designed to fit a 17-inch wheel.