Blackhawk 225/45 R18″ refers to a specific tire size and model. Here’s a breakdown of what each part of the designation represents:

225: This number indicates the width of the tire in millimeters. In this case, the tire’s width is 225 millimeters.

45: This number denotes the aspect ratio of the tire, which represents the height of the tire’s sidewall as a percentage of the tire’s width. The sidewall height is 45% of the tire’s width.

R: This letter signifies the construction type of the tire. The “R” stands for radial construction, which is the standard construction for modern tires.

18: This number corresponds to the diameter of the wheel, in inches, on which the tire is intended to be mounted. In this instance, the tire is designed for an 18-inch wheel.

As always, it’s important to ensure that any new tires are suitable for the vehicle and the intended use. Professional advice can help in confirming the compatibility of the tires with the vehicle’s specifications and driving conditions.